xref: /freebsd/contrib/llvm-project/libcxx/include/algorithm (revision e40139ff33b48b56a24c808b166b04b8ee6f5b21)
10b57cec5SDimitry Andric// -*- C++ -*-
20b57cec5SDimitry Andric//===-------------------------- algorithm ---------------------------------===//
30b57cec5SDimitry Andric//
40b57cec5SDimitry Andric// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
50b57cec5SDimitry Andric// See https://llvm.org/LICENSE.txt for license information.
60b57cec5SDimitry Andric// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
70b57cec5SDimitry Andric//
80b57cec5SDimitry Andric//===----------------------------------------------------------------------===//
90b57cec5SDimitry Andric
100b57cec5SDimitry Andric#ifndef _LIBCPP_ALGORITHM
110b57cec5SDimitry Andric#define _LIBCPP_ALGORITHM
120b57cec5SDimitry Andric
130b57cec5SDimitry Andric/*
140b57cec5SDimitry Andric    algorithm synopsis
150b57cec5SDimitry Andric
160b57cec5SDimitry Andric#include <initializer_list>
170b57cec5SDimitry Andric
180b57cec5SDimitry Andricnamespace std
190b57cec5SDimitry Andric{
200b57cec5SDimitry Andric
210b57cec5SDimitry Andrictemplate <class InputIterator, class Predicate>
220b57cec5SDimitry Andric    constexpr bool     // constexpr in C++20
230b57cec5SDimitry Andric    all_of(InputIterator first, InputIterator last, Predicate pred);
240b57cec5SDimitry Andric
250b57cec5SDimitry Andrictemplate <class InputIterator, class Predicate>
260b57cec5SDimitry Andric    constexpr bool     // constexpr in C++20
270b57cec5SDimitry Andric    any_of(InputIterator first, InputIterator last, Predicate pred);
280b57cec5SDimitry Andric
290b57cec5SDimitry Andrictemplate <class InputIterator, class Predicate>
300b57cec5SDimitry Andric    constexpr bool     // constexpr in C++20
310b57cec5SDimitry Andric    none_of(InputIterator first, InputIterator last, Predicate pred);
320b57cec5SDimitry Andric
330b57cec5SDimitry Andrictemplate <class InputIterator, class Function>
340b57cec5SDimitry Andric    constexpr Function          // constexpr in C++20
350b57cec5SDimitry Andric    for_each(InputIterator first, InputIterator last, Function f);
360b57cec5SDimitry Andric
370b57cec5SDimitry Andrictemplate<class InputIterator, class Size, class Function>
380b57cec5SDimitry Andric    constexpr InputIterator     // constexpr in C++20
390b57cec5SDimitry Andric    for_each_n(InputIterator first, Size n, Function f); // C++17
400b57cec5SDimitry Andric
410b57cec5SDimitry Andrictemplate <class InputIterator, class T>
420b57cec5SDimitry Andric    constexpr InputIterator     // constexpr in C++20
430b57cec5SDimitry Andric    find(InputIterator first, InputIterator last, const T& value);
440b57cec5SDimitry Andric
450b57cec5SDimitry Andrictemplate <class InputIterator, class Predicate>
460b57cec5SDimitry Andric    constexpr InputIterator     // constexpr in C++20
470b57cec5SDimitry Andric    find_if(InputIterator first, InputIterator last, Predicate pred);
480b57cec5SDimitry Andric
490b57cec5SDimitry Andrictemplate<class InputIterator, class Predicate>
500b57cec5SDimitry Andric    InputIterator               // constexpr in C++20
510b57cec5SDimitry Andric    find_if_not(InputIterator first, InputIterator last, Predicate pred);
520b57cec5SDimitry Andric
530b57cec5SDimitry Andrictemplate <class ForwardIterator1, class ForwardIterator2>
540b57cec5SDimitry Andric    ForwardIterator1            // constexpr in C++20
550b57cec5SDimitry Andric    find_end(ForwardIterator1 first1, ForwardIterator1 last1,
560b57cec5SDimitry Andric             ForwardIterator2 first2, ForwardIterator2 last2);
570b57cec5SDimitry Andric
580b57cec5SDimitry Andrictemplate <class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
590b57cec5SDimitry Andric    ForwardIterator1            // constexpr in C++20
600b57cec5SDimitry Andric    find_end(ForwardIterator1 first1, ForwardIterator1 last1,
610b57cec5SDimitry Andric             ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);
620b57cec5SDimitry Andric
630b57cec5SDimitry Andrictemplate <class ForwardIterator1, class ForwardIterator2>
640b57cec5SDimitry Andric    constexpr ForwardIterator1  // constexpr in C++20
650b57cec5SDimitry Andric    find_first_of(ForwardIterator1 first1, ForwardIterator1 last1,
660b57cec5SDimitry Andric                  ForwardIterator2 first2, ForwardIterator2 last2);
670b57cec5SDimitry Andric
680b57cec5SDimitry Andrictemplate <class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
690b57cec5SDimitry Andric    constexpr ForwardIterator1  // constexpr in C++20
700b57cec5SDimitry Andric    find_first_of(ForwardIterator1 first1, ForwardIterator1 last1,
710b57cec5SDimitry Andric                  ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);
720b57cec5SDimitry Andric
730b57cec5SDimitry Andrictemplate <class ForwardIterator>
740b57cec5SDimitry Andric    constexpr ForwardIterator   // constexpr in C++20
750b57cec5SDimitry Andric    adjacent_find(ForwardIterator first, ForwardIterator last);
760b57cec5SDimitry Andric
770b57cec5SDimitry Andrictemplate <class ForwardIterator, class BinaryPredicate>
780b57cec5SDimitry Andric    constexpr ForwardIterator   // constexpr in C++20
790b57cec5SDimitry Andric    adjacent_find(ForwardIterator first, ForwardIterator last, BinaryPredicate pred);
800b57cec5SDimitry Andric
810b57cec5SDimitry Andrictemplate <class InputIterator, class T>
820b57cec5SDimitry Andric    constexpr typename iterator_traits<InputIterator>::difference_type  // constexpr in C++20
830b57cec5SDimitry Andric    count(InputIterator first, InputIterator last, const T& value);
840b57cec5SDimitry Andric
850b57cec5SDimitry Andrictemplate <class InputIterator, class Predicate>
860b57cec5SDimitry Andric    constexpr typename iterator_traits<InputIterator>::difference_type // constexpr in C++20
870b57cec5SDimitry Andric    count_if(InputIterator first, InputIterator last, Predicate pred);
880b57cec5SDimitry Andric
890b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2>
900b57cec5SDimitry Andric    constexpr pair<InputIterator1, InputIterator2>   // constexpr in C++20
910b57cec5SDimitry Andric    mismatch(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2);
920b57cec5SDimitry Andric
930b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2>
940b57cec5SDimitry Andric    constexpr pair<InputIterator1, InputIterator2>   // constexpr in C++20
950b57cec5SDimitry Andric    mismatch(InputIterator1 first1, InputIterator1 last1,
960b57cec5SDimitry Andric             InputIterator2 first2, InputIterator2 last2); // **C++14**
970b57cec5SDimitry Andric
980b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2, class BinaryPredicate>
990b57cec5SDimitry Andric    constexpr pair<InputIterator1, InputIterator2>   // constexpr in C++20
1000b57cec5SDimitry Andric    mismatch(InputIterator1 first1, InputIterator1 last1,
1010b57cec5SDimitry Andric             InputIterator2 first2, BinaryPredicate pred);
1020b57cec5SDimitry Andric
1030b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2, class BinaryPredicate>
1040b57cec5SDimitry Andric    constexpr pair<InputIterator1, InputIterator2>   // constexpr in C++20
1050b57cec5SDimitry Andric    mismatch(InputIterator1 first1, InputIterator1 last1,
1060b57cec5SDimitry Andric             InputIterator2 first2, InputIterator2 last2,
1070b57cec5SDimitry Andric             BinaryPredicate pred); // **C++14**
1080b57cec5SDimitry Andric
1090b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2>
1100b57cec5SDimitry Andric    constexpr bool      // constexpr in C++20
1110b57cec5SDimitry Andric    equal(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2);
1120b57cec5SDimitry Andric
1130b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2>
1140b57cec5SDimitry Andric    constexpr bool      // constexpr in C++20
1150b57cec5SDimitry Andric    equal(InputIterator1 first1, InputIterator1 last1,
1160b57cec5SDimitry Andric          InputIterator2 first2, InputIterator2 last2); // **C++14**
1170b57cec5SDimitry Andric
1180b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2, class BinaryPredicate>
1190b57cec5SDimitry Andric    constexpr bool      // constexpr in C++20
1200b57cec5SDimitry Andric    equal(InputIterator1 first1, InputIterator1 last1,
1210b57cec5SDimitry Andric          InputIterator2 first2, BinaryPredicate pred);
1220b57cec5SDimitry Andric
1230b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2, class BinaryPredicate>
1240b57cec5SDimitry Andric    constexpr bool      // constexpr in C++20
1250b57cec5SDimitry Andric    equal(InputIterator1 first1, InputIterator1 last1,
1260b57cec5SDimitry Andric          InputIterator2 first2, InputIterator2 last2,
1270b57cec5SDimitry Andric          BinaryPredicate pred); // **C++14**
1280b57cec5SDimitry Andric
1290b57cec5SDimitry Andrictemplate<class ForwardIterator1, class ForwardIterator2>
1300b57cec5SDimitry Andric    constexpr bool      // constexpr in C++20
1310b57cec5SDimitry Andric    is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
1320b57cec5SDimitry Andric                   ForwardIterator2 first2);
1330b57cec5SDimitry Andric
1340b57cec5SDimitry Andrictemplate<class ForwardIterator1, class ForwardIterator2>
1350b57cec5SDimitry Andric    constexpr bool      // constexpr in C++20
1360b57cec5SDimitry Andric    is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
1370b57cec5SDimitry Andric                   ForwardIterator2 first2, ForwardIterator2 last2); // **C++14**
1380b57cec5SDimitry Andric
1390b57cec5SDimitry Andrictemplate<class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
1400b57cec5SDimitry Andric    constexpr bool      // constexpr in C++20
1410b57cec5SDimitry Andric    is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
1420b57cec5SDimitry Andric                   ForwardIterator2 first2, BinaryPredicate pred);
1430b57cec5SDimitry Andric
1440b57cec5SDimitry Andrictemplate<class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
1450b57cec5SDimitry Andric    constexpr bool      // constexpr in C++20
1460b57cec5SDimitry Andric    is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
1470b57cec5SDimitry Andric                   ForwardIterator2 first2, ForwardIterator2 last2,
1480b57cec5SDimitry Andric                   BinaryPredicate pred);  // **C++14**
1490b57cec5SDimitry Andric
1500b57cec5SDimitry Andrictemplate <class ForwardIterator1, class ForwardIterator2>
1510b57cec5SDimitry Andric    constexpr ForwardIterator1      // constexpr in C++20
1520b57cec5SDimitry Andric    search(ForwardIterator1 first1, ForwardIterator1 last1,
1530b57cec5SDimitry Andric           ForwardIterator2 first2, ForwardIterator2 last2);
1540b57cec5SDimitry Andric
1550b57cec5SDimitry Andrictemplate <class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
1560b57cec5SDimitry Andric    constexpr ForwardIterator1      // constexpr in C++20
1570b57cec5SDimitry Andric    search(ForwardIterator1 first1, ForwardIterator1 last1,
1580b57cec5SDimitry Andric           ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);
1590b57cec5SDimitry Andric
1600b57cec5SDimitry Andrictemplate <class ForwardIterator, class Size, class T>
1610b57cec5SDimitry Andric    constexpr ForwardIterator       // constexpr in C++20
1620b57cec5SDimitry Andric    search_n(ForwardIterator first, ForwardIterator last, Size count, const T& value);
1630b57cec5SDimitry Andric
1640b57cec5SDimitry Andrictemplate <class ForwardIterator, class Size, class T, class BinaryPredicate>
1650b57cec5SDimitry Andric    constexpr ForwardIterator       // constexpr in C++20
1660b57cec5SDimitry Andric    search_n(ForwardIterator first, ForwardIterator last,
1670b57cec5SDimitry Andric             Size count, const T& value, BinaryPredicate pred);
1680b57cec5SDimitry Andric
1690b57cec5SDimitry Andrictemplate <class InputIterator, class OutputIterator>
1700b57cec5SDimitry Andric    OutputIterator
1710b57cec5SDimitry Andric    copy(InputIterator first, InputIterator last, OutputIterator result);
1720b57cec5SDimitry Andric
1730b57cec5SDimitry Andrictemplate<class InputIterator, class OutputIterator, class Predicate>
1740b57cec5SDimitry Andric    OutputIterator
1750b57cec5SDimitry Andric    copy_if(InputIterator first, InputIterator last,
1760b57cec5SDimitry Andric            OutputIterator result, Predicate pred);
1770b57cec5SDimitry Andric
1780b57cec5SDimitry Andrictemplate<class InputIterator, class Size, class OutputIterator>
1790b57cec5SDimitry Andric    OutputIterator
1800b57cec5SDimitry Andric    copy_n(InputIterator first, Size n, OutputIterator result);
1810b57cec5SDimitry Andric
1820b57cec5SDimitry Andrictemplate <class BidirectionalIterator1, class BidirectionalIterator2>
1830b57cec5SDimitry Andric    BidirectionalIterator2
1840b57cec5SDimitry Andric    copy_backward(BidirectionalIterator1 first, BidirectionalIterator1 last,
1850b57cec5SDimitry Andric                  BidirectionalIterator2 result);
1860b57cec5SDimitry Andric
1870b57cec5SDimitry Andrictemplate <class ForwardIterator1, class ForwardIterator2>
1880b57cec5SDimitry Andric    ForwardIterator2
1890b57cec5SDimitry Andric    swap_ranges(ForwardIterator1 first1, ForwardIterator1 last1, ForwardIterator2 first2);
1900b57cec5SDimitry Andric
1910b57cec5SDimitry Andrictemplate <class ForwardIterator1, class ForwardIterator2>
1920b57cec5SDimitry Andric    void
1930b57cec5SDimitry Andric    iter_swap(ForwardIterator1 a, ForwardIterator2 b);
1940b57cec5SDimitry Andric
1950b57cec5SDimitry Andrictemplate <class InputIterator, class OutputIterator, class UnaryOperation>
1960b57cec5SDimitry Andric    constexpr OutputIterator      // constexpr in C++20
1970b57cec5SDimitry Andric    transform(InputIterator first, InputIterator last, OutputIterator result, UnaryOperation op);
1980b57cec5SDimitry Andric
1990b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2, class OutputIterator, class BinaryOperation>
2000b57cec5SDimitry Andric    constexpr OutputIterator      // constexpr in C++20
2010b57cec5SDimitry Andric    transform(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2,
2020b57cec5SDimitry Andric              OutputIterator result, BinaryOperation binary_op);
2030b57cec5SDimitry Andric
2040b57cec5SDimitry Andrictemplate <class ForwardIterator, class T>
2050b57cec5SDimitry Andric    constexpr void      // constexpr in C++20
2060b57cec5SDimitry Andric    replace(ForwardIterator first, ForwardIterator last, const T& old_value, const T& new_value);
2070b57cec5SDimitry Andric
2080b57cec5SDimitry Andrictemplate <class ForwardIterator, class Predicate, class T>
2090b57cec5SDimitry Andric    constexpr void      // constexpr in C++20
2100b57cec5SDimitry Andric    replace_if(ForwardIterator first, ForwardIterator last, Predicate pred, const T& new_value);
2110b57cec5SDimitry Andric
2120b57cec5SDimitry Andrictemplate <class InputIterator, class OutputIterator, class T>
2130b57cec5SDimitry Andric    constexpr OutputIterator      // constexpr in C++20
2140b57cec5SDimitry Andric    replace_copy(InputIterator first, InputIterator last, OutputIterator result,
2150b57cec5SDimitry Andric                 const T& old_value, const T& new_value);
2160b57cec5SDimitry Andric
2170b57cec5SDimitry Andrictemplate <class InputIterator, class OutputIterator, class Predicate, class T>
2180b57cec5SDimitry Andric    constexpr OutputIterator      // constexpr in C++20
2190b57cec5SDimitry Andric    replace_copy_if(InputIterator first, InputIterator last, OutputIterator result, Predicate pred, const T& new_value);
2200b57cec5SDimitry Andric
2210b57cec5SDimitry Andrictemplate <class ForwardIterator, class T>
2220b57cec5SDimitry Andric    constexpr void      // constexpr in C++20
2230b57cec5SDimitry Andric    fill(ForwardIterator first, ForwardIterator last, const T& value);
2240b57cec5SDimitry Andric
2250b57cec5SDimitry Andrictemplate <class OutputIterator, class Size, class T>
2260b57cec5SDimitry Andric    constexpr OutputIterator      // constexpr in C++20
2270b57cec5SDimitry Andric    fill_n(OutputIterator first, Size n, const T& value);
2280b57cec5SDimitry Andric
2290b57cec5SDimitry Andrictemplate <class ForwardIterator, class Generator>
2300b57cec5SDimitry Andric    constexpr void      // constexpr in C++20
2310b57cec5SDimitry Andric    generate(ForwardIterator first, ForwardIterator last, Generator gen);
2320b57cec5SDimitry Andric
2330b57cec5SDimitry Andrictemplate <class OutputIterator, class Size, class Generator>
2340b57cec5SDimitry Andric    constexpr OutputIterator      // constexpr in C++20
2350b57cec5SDimitry Andric    generate_n(OutputIterator first, Size n, Generator gen);
2360b57cec5SDimitry Andric
2370b57cec5SDimitry Andrictemplate <class ForwardIterator, class T>
2380b57cec5SDimitry Andric    constexpr ForwardIterator     // constexpr in C++20
2390b57cec5SDimitry Andric    remove(ForwardIterator first, ForwardIterator last, const T& value);
2400b57cec5SDimitry Andric
2410b57cec5SDimitry Andrictemplate <class ForwardIterator, class Predicate>
2420b57cec5SDimitry Andric    constexpr ForwardIterator     // constexpr in C++20
2430b57cec5SDimitry Andric    remove_if(ForwardIterator first, ForwardIterator last, Predicate pred);
2440b57cec5SDimitry Andric
2450b57cec5SDimitry Andrictemplate <class InputIterator, class OutputIterator, class T>
2460b57cec5SDimitry Andric    constexpr OutputIterator     // constexpr in C++20
2470b57cec5SDimitry Andric    remove_copy(InputIterator first, InputIterator last, OutputIterator result, const T& value);
2480b57cec5SDimitry Andric
2490b57cec5SDimitry Andrictemplate <class InputIterator, class OutputIterator, class Predicate>
2500b57cec5SDimitry Andric    constexpr OutputIterator     // constexpr in C++20
2510b57cec5SDimitry Andric    remove_copy_if(InputIterator first, InputIterator last, OutputIterator result, Predicate pred);
2520b57cec5SDimitry Andric
2530b57cec5SDimitry Andrictemplate <class ForwardIterator>
2540b57cec5SDimitry Andric    ForwardIterator
2550b57cec5SDimitry Andric    unique(ForwardIterator first, ForwardIterator last);
2560b57cec5SDimitry Andric
2570b57cec5SDimitry Andrictemplate <class ForwardIterator, class BinaryPredicate>
2580b57cec5SDimitry Andric    ForwardIterator
2590b57cec5SDimitry Andric    unique(ForwardIterator first, ForwardIterator last, BinaryPredicate pred);
2600b57cec5SDimitry Andric
2610b57cec5SDimitry Andrictemplate <class InputIterator, class OutputIterator>
2620b57cec5SDimitry Andric    OutputIterator
2630b57cec5SDimitry Andric    unique_copy(InputIterator first, InputIterator last, OutputIterator result);
2640b57cec5SDimitry Andric
2650b57cec5SDimitry Andrictemplate <class InputIterator, class OutputIterator, class BinaryPredicate>
2660b57cec5SDimitry Andric    OutputIterator
2670b57cec5SDimitry Andric    unique_copy(InputIterator first, InputIterator last, OutputIterator result, BinaryPredicate pred);
2680b57cec5SDimitry Andric
2690b57cec5SDimitry Andrictemplate <class BidirectionalIterator>
2700b57cec5SDimitry Andric    void
2710b57cec5SDimitry Andric    reverse(BidirectionalIterator first, BidirectionalIterator last);
2720b57cec5SDimitry Andric
2730b57cec5SDimitry Andrictemplate <class BidirectionalIterator, class OutputIterator>
2740b57cec5SDimitry Andric    constexpr OutputIterator       // constexpr in C++20
2750b57cec5SDimitry Andric    reverse_copy(BidirectionalIterator first, BidirectionalIterator last, OutputIterator result);
2760b57cec5SDimitry Andric
2770b57cec5SDimitry Andrictemplate <class ForwardIterator>
2780b57cec5SDimitry Andric    ForwardIterator
2790b57cec5SDimitry Andric    rotate(ForwardIterator first, ForwardIterator middle, ForwardIterator last);
2800b57cec5SDimitry Andric
2810b57cec5SDimitry Andrictemplate <class ForwardIterator, class OutputIterator>
2820b57cec5SDimitry Andric    OutputIterator
2830b57cec5SDimitry Andric    rotate_copy(ForwardIterator first, ForwardIterator middle, ForwardIterator last, OutputIterator result);
2840b57cec5SDimitry Andric
2850b57cec5SDimitry Andrictemplate <class RandomAccessIterator>
2860b57cec5SDimitry Andric    void
2870b57cec5SDimitry Andric    random_shuffle(RandomAccessIterator first, RandomAccessIterator last); // deprecated in C++14, removed in C++17
2880b57cec5SDimitry Andric
2890b57cec5SDimitry Andrictemplate <class RandomAccessIterator, class RandomNumberGenerator>
2900b57cec5SDimitry Andric    void
2910b57cec5SDimitry Andric    random_shuffle(RandomAccessIterator first, RandomAccessIterator last,
2920b57cec5SDimitry Andric                   RandomNumberGenerator& rand);  // deprecated in C++14, removed in C++17
2930b57cec5SDimitry Andric
2940b57cec5SDimitry Andrictemplate<class PopulationIterator, class SampleIterator,
2950b57cec5SDimitry Andric         class Distance, class UniformRandomBitGenerator>
2960b57cec5SDimitry Andric    SampleIterator sample(PopulationIterator first, PopulationIterator last,
2970b57cec5SDimitry Andric                          SampleIterator out, Distance n,
2980b57cec5SDimitry Andric                          UniformRandomBitGenerator&& g); // C++17
2990b57cec5SDimitry Andric
3000b57cec5SDimitry Andrictemplate<class RandomAccessIterator, class UniformRandomNumberGenerator>
3010b57cec5SDimitry Andric    void shuffle(RandomAccessIterator first, RandomAccessIterator last,
3020b57cec5SDimitry Andric                 UniformRandomNumberGenerator&& g);
3030b57cec5SDimitry Andric
3040b57cec5SDimitry Andrictemplate <class InputIterator, class Predicate>
3050b57cec5SDimitry Andric    constexpr bool  // constexpr in C++20
3060b57cec5SDimitry Andric    is_partitioned(InputIterator first, InputIterator last, Predicate pred);
3070b57cec5SDimitry Andric
3080b57cec5SDimitry Andrictemplate <class ForwardIterator, class Predicate>
3090b57cec5SDimitry Andric    ForwardIterator
3100b57cec5SDimitry Andric    partition(ForwardIterator first, ForwardIterator last, Predicate pred);
3110b57cec5SDimitry Andric
3120b57cec5SDimitry Andrictemplate <class InputIterator, class OutputIterator1,
3130b57cec5SDimitry Andric          class OutputIterator2, class Predicate>
3140b57cec5SDimitry Andric    constexpr pair<OutputIterator1, OutputIterator2>   // constexpr in C++20
3150b57cec5SDimitry Andric    partition_copy(InputIterator first, InputIterator last,
3160b57cec5SDimitry Andric                   OutputIterator1 out_true, OutputIterator2 out_false,
3170b57cec5SDimitry Andric                   Predicate pred);
3180b57cec5SDimitry Andric
3190b57cec5SDimitry Andrictemplate <class ForwardIterator, class Predicate>
3200b57cec5SDimitry Andric    ForwardIterator
3210b57cec5SDimitry Andric    stable_partition(ForwardIterator first, ForwardIterator last, Predicate pred);
3220b57cec5SDimitry Andric
3230b57cec5SDimitry Andrictemplate<class ForwardIterator, class Predicate>
3240b57cec5SDimitry Andric    constexpr ForwardIterator  // constexpr in C++20
3250b57cec5SDimitry Andric    partition_point(ForwardIterator first, ForwardIterator last, Predicate pred);
3260b57cec5SDimitry Andric
3270b57cec5SDimitry Andrictemplate <class ForwardIterator>
3280b57cec5SDimitry Andric    constexpr bool  // constexpr in C++20
3290b57cec5SDimitry Andric    is_sorted(ForwardIterator first, ForwardIterator last);
3300b57cec5SDimitry Andric
3310b57cec5SDimitry Andrictemplate <class ForwardIterator, class Compare>
3320b57cec5SDimitry Andric    bool
3330b57cec5SDimitry Andric    is_sorted(ForwardIterator first, ForwardIterator last, Compare comp);
3340b57cec5SDimitry Andric
3350b57cec5SDimitry Andrictemplate<class ForwardIterator>
3360b57cec5SDimitry Andric    constexpr ForwardIterator    // constexpr in C++20
3370b57cec5SDimitry Andric    is_sorted_until(ForwardIterator first, ForwardIterator last);
3380b57cec5SDimitry Andric
3390b57cec5SDimitry Andrictemplate <class ForwardIterator, class Compare>
3400b57cec5SDimitry Andric    constexpr ForwardIterator    // constexpr in C++20
3410b57cec5SDimitry Andric    is_sorted_until(ForwardIterator first, ForwardIterator last, Compare comp);
3420b57cec5SDimitry Andric
3430b57cec5SDimitry Andrictemplate <class RandomAccessIterator>
3440b57cec5SDimitry Andric    void
3450b57cec5SDimitry Andric    sort(RandomAccessIterator first, RandomAccessIterator last);
3460b57cec5SDimitry Andric
3470b57cec5SDimitry Andrictemplate <class RandomAccessIterator, class Compare>
3480b57cec5SDimitry Andric    void
3490b57cec5SDimitry Andric    sort(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
3500b57cec5SDimitry Andric
3510b57cec5SDimitry Andrictemplate <class RandomAccessIterator>
3520b57cec5SDimitry Andric    void
3530b57cec5SDimitry Andric    stable_sort(RandomAccessIterator first, RandomAccessIterator last);
3540b57cec5SDimitry Andric
3550b57cec5SDimitry Andrictemplate <class RandomAccessIterator, class Compare>
3560b57cec5SDimitry Andric    void
3570b57cec5SDimitry Andric    stable_sort(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
3580b57cec5SDimitry Andric
3590b57cec5SDimitry Andrictemplate <class RandomAccessIterator>
3600b57cec5SDimitry Andric    void
3610b57cec5SDimitry Andric    partial_sort(RandomAccessIterator first, RandomAccessIterator middle, RandomAccessIterator last);
3620b57cec5SDimitry Andric
3630b57cec5SDimitry Andrictemplate <class RandomAccessIterator, class Compare>
3640b57cec5SDimitry Andric    void
3650b57cec5SDimitry Andric    partial_sort(RandomAccessIterator first, RandomAccessIterator middle, RandomAccessIterator last, Compare comp);
3660b57cec5SDimitry Andric
3670b57cec5SDimitry Andrictemplate <class InputIterator, class RandomAccessIterator>
3680b57cec5SDimitry Andric    RandomAccessIterator
3690b57cec5SDimitry Andric    partial_sort_copy(InputIterator first, InputIterator last,
3700b57cec5SDimitry Andric                      RandomAccessIterator result_first, RandomAccessIterator result_last);
3710b57cec5SDimitry Andric
3720b57cec5SDimitry Andrictemplate <class InputIterator, class RandomAccessIterator, class Compare>
3730b57cec5SDimitry Andric    RandomAccessIterator
3740b57cec5SDimitry Andric    partial_sort_copy(InputIterator first, InputIterator last,
3750b57cec5SDimitry Andric                      RandomAccessIterator result_first, RandomAccessIterator result_last, Compare comp);
3760b57cec5SDimitry Andric
3770b57cec5SDimitry Andrictemplate <class RandomAccessIterator>
3780b57cec5SDimitry Andric    void
3790b57cec5SDimitry Andric    nth_element(RandomAccessIterator first, RandomAccessIterator nth, RandomAccessIterator last);
3800b57cec5SDimitry Andric
3810b57cec5SDimitry Andrictemplate <class RandomAccessIterator, class Compare>
3820b57cec5SDimitry Andric    void
3830b57cec5SDimitry Andric    nth_element(RandomAccessIterator first, RandomAccessIterator nth, RandomAccessIterator last, Compare comp);
3840b57cec5SDimitry Andric
3850b57cec5SDimitry Andrictemplate <class ForwardIterator, class T>
3860b57cec5SDimitry Andric    constexpr ForwardIterator                         // constexpr in C++20
3870b57cec5SDimitry Andric    lower_bound(ForwardIterator first, ForwardIterator last, const T& value);
3880b57cec5SDimitry Andric
3890b57cec5SDimitry Andrictemplate <class ForwardIterator, class T, class Compare>
3900b57cec5SDimitry Andric    constexpr ForwardIterator                         // constexpr in C++20
3910b57cec5SDimitry Andric    lower_bound(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
3920b57cec5SDimitry Andric
3930b57cec5SDimitry Andrictemplate <class ForwardIterator, class T>
3940b57cec5SDimitry Andric    constexpr ForwardIterator                         // constexpr in C++20
3950b57cec5SDimitry Andric    upper_bound(ForwardIterator first, ForwardIterator last, const T& value);
3960b57cec5SDimitry Andric
3970b57cec5SDimitry Andrictemplate <class ForwardIterator, class T, class Compare>
3980b57cec5SDimitry Andric    constexpr ForwardIterator                         // constexpr in C++20
3990b57cec5SDimitry Andric    upper_bound(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
4000b57cec5SDimitry Andric
4010b57cec5SDimitry Andrictemplate <class ForwardIterator, class T>
4020b57cec5SDimitry Andric    constexpr pair<ForwardIterator, ForwardIterator>  // constexpr in C++20
4030b57cec5SDimitry Andric    equal_range(ForwardIterator first, ForwardIterator last, const T& value);
4040b57cec5SDimitry Andric
4050b57cec5SDimitry Andrictemplate <class ForwardIterator, class T, class Compare>
4060b57cec5SDimitry Andric    constexpr pair<ForwardIterator, ForwardIterator>  // constexpr in C++20
4070b57cec5SDimitry Andric    equal_range(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
4080b57cec5SDimitry Andric
4090b57cec5SDimitry Andrictemplate <class ForwardIterator, class T>
4100b57cec5SDimitry Andric    constexpr bool                                    // constexpr in C++20
4110b57cec5SDimitry Andric    binary_search(ForwardIterator first, ForwardIterator last, const T& value);
4120b57cec5SDimitry Andric
4130b57cec5SDimitry Andrictemplate <class ForwardIterator, class T, class Compare>
4140b57cec5SDimitry Andric    constexpr bool                                    // constexpr in C++20
4150b57cec5SDimitry Andric    binary_search(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
4160b57cec5SDimitry Andric
4170b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2, class OutputIterator>
4180b57cec5SDimitry Andric    OutputIterator
4190b57cec5SDimitry Andric    merge(InputIterator1 first1, InputIterator1 last1,
4200b57cec5SDimitry Andric          InputIterator2 first2, InputIterator2 last2, OutputIterator result);
4210b57cec5SDimitry Andric
4220b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
4230b57cec5SDimitry Andric    OutputIterator
4240b57cec5SDimitry Andric    merge(InputIterator1 first1, InputIterator1 last1,
4250b57cec5SDimitry Andric          InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
4260b57cec5SDimitry Andric
4270b57cec5SDimitry Andrictemplate <class BidirectionalIterator>
4280b57cec5SDimitry Andric    void
4290b57cec5SDimitry Andric    inplace_merge(BidirectionalIterator first, BidirectionalIterator middle, BidirectionalIterator last);
4300b57cec5SDimitry Andric
4310b57cec5SDimitry Andrictemplate <class BidirectionalIterator, class Compare>
4320b57cec5SDimitry Andric    void
4330b57cec5SDimitry Andric    inplace_merge(BidirectionalIterator first, BidirectionalIterator middle, BidirectionalIterator last, Compare comp);
4340b57cec5SDimitry Andric
4350b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2>
4360b57cec5SDimitry Andric    constexpr bool                                    // constexpr in C++20
4370b57cec5SDimitry Andric    includes(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2);
4380b57cec5SDimitry Andric
4390b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2, class Compare>
4400b57cec5SDimitry Andric    constexpr bool                                    // constexpr in C++20
4410b57cec5SDimitry Andric    includes(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2, Compare comp);
4420b57cec5SDimitry Andric
4430b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2, class OutputIterator>
4440b57cec5SDimitry Andric    OutputIterator
4450b57cec5SDimitry Andric    set_union(InputIterator1 first1, InputIterator1 last1,
4460b57cec5SDimitry Andric              InputIterator2 first2, InputIterator2 last2, OutputIterator result);
4470b57cec5SDimitry Andric
4480b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
4490b57cec5SDimitry Andric    OutputIterator
4500b57cec5SDimitry Andric    set_union(InputIterator1 first1, InputIterator1 last1,
4510b57cec5SDimitry Andric              InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
4520b57cec5SDimitry Andric
4530b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2, class OutputIterator>
4540b57cec5SDimitry Andric    constexpr OutputIterator                         // constexpr in C++20
4550b57cec5SDimitry Andric    set_intersection(InputIterator1 first1, InputIterator1 last1,
4560b57cec5SDimitry Andric                     InputIterator2 first2, InputIterator2 last2, OutputIterator result);
4570b57cec5SDimitry Andric
4580b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
4590b57cec5SDimitry Andric    constexpr OutputIterator                         // constexpr in C++20
4600b57cec5SDimitry Andric    set_intersection(InputIterator1 first1, InputIterator1 last1,
4610b57cec5SDimitry Andric                     InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
4620b57cec5SDimitry Andric
4630b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2, class OutputIterator>
4640b57cec5SDimitry Andric    OutputIterator
4650b57cec5SDimitry Andric    set_difference(InputIterator1 first1, InputIterator1 last1,
4660b57cec5SDimitry Andric                   InputIterator2 first2, InputIterator2 last2, OutputIterator result);
4670b57cec5SDimitry Andric
4680b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
4690b57cec5SDimitry Andric    OutputIterator
4700b57cec5SDimitry Andric    set_difference(InputIterator1 first1, InputIterator1 last1,
4710b57cec5SDimitry Andric                   InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
4720b57cec5SDimitry Andric
4730b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2, class OutputIterator>
4740b57cec5SDimitry Andric    OutputIterator
4750b57cec5SDimitry Andric    set_symmetric_difference(InputIterator1 first1, InputIterator1 last1,
4760b57cec5SDimitry Andric                             InputIterator2 first2, InputIterator2 last2, OutputIterator result);
4770b57cec5SDimitry Andric
4780b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
4790b57cec5SDimitry Andric    OutputIterator
4800b57cec5SDimitry Andric    set_symmetric_difference(InputIterator1 first1, InputIterator1 last1,
4810b57cec5SDimitry Andric                             InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
4820b57cec5SDimitry Andric
4830b57cec5SDimitry Andrictemplate <class RandomAccessIterator>
4840b57cec5SDimitry Andric    void
4850b57cec5SDimitry Andric    push_heap(RandomAccessIterator first, RandomAccessIterator last);
4860b57cec5SDimitry Andric
4870b57cec5SDimitry Andrictemplate <class RandomAccessIterator, class Compare>
4880b57cec5SDimitry Andric    void
4890b57cec5SDimitry Andric    push_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
4900b57cec5SDimitry Andric
4910b57cec5SDimitry Andrictemplate <class RandomAccessIterator>
4920b57cec5SDimitry Andric    void
4930b57cec5SDimitry Andric    pop_heap(RandomAccessIterator first, RandomAccessIterator last);
4940b57cec5SDimitry Andric
4950b57cec5SDimitry Andrictemplate <class RandomAccessIterator, class Compare>
4960b57cec5SDimitry Andric    void
4970b57cec5SDimitry Andric    pop_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
4980b57cec5SDimitry Andric
4990b57cec5SDimitry Andrictemplate <class RandomAccessIterator>
5000b57cec5SDimitry Andric    void
5010b57cec5SDimitry Andric    make_heap(RandomAccessIterator first, RandomAccessIterator last);
5020b57cec5SDimitry Andric
5030b57cec5SDimitry Andrictemplate <class RandomAccessIterator, class Compare>
5040b57cec5SDimitry Andric    void
5050b57cec5SDimitry Andric    make_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
5060b57cec5SDimitry Andric
5070b57cec5SDimitry Andrictemplate <class RandomAccessIterator>
5080b57cec5SDimitry Andric    void
5090b57cec5SDimitry Andric    sort_heap(RandomAccessIterator first, RandomAccessIterator last);
5100b57cec5SDimitry Andric
5110b57cec5SDimitry Andrictemplate <class RandomAccessIterator, class Compare>
5120b57cec5SDimitry Andric    void
5130b57cec5SDimitry Andric    sort_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
5140b57cec5SDimitry Andric
5150b57cec5SDimitry Andrictemplate <class RandomAccessIterator>
5160b57cec5SDimitry Andric    constexpr bool   // constexpr in C++20
5170b57cec5SDimitry Andric    is_heap(RandomAccessIterator first, RandomAccessiterator last);
5180b57cec5SDimitry Andric
5190b57cec5SDimitry Andrictemplate <class RandomAccessIterator, class Compare>
5200b57cec5SDimitry Andric    constexpr bool   // constexpr in C++20
5210b57cec5SDimitry Andric    is_heap(RandomAccessIterator first, RandomAccessiterator last, Compare comp);
5220b57cec5SDimitry Andric
5230b57cec5SDimitry Andrictemplate <class RandomAccessIterator>
5240b57cec5SDimitry Andric    constexpr RandomAccessIterator   // constexpr in C++20
5250b57cec5SDimitry Andric    is_heap_until(RandomAccessIterator first, RandomAccessiterator last);
5260b57cec5SDimitry Andric
5270b57cec5SDimitry Andrictemplate <class RandomAccessIterator, class Compare>
5280b57cec5SDimitry Andric    constexpr RandomAccessIterator   // constexpr in C++20
5290b57cec5SDimitry Andric    is_heap_until(RandomAccessIterator first, RandomAccessiterator last, Compare comp);
5300b57cec5SDimitry Andric
5310b57cec5SDimitry Andrictemplate <class ForwardIterator>
5320b57cec5SDimitry Andric    ForwardIterator
5330b57cec5SDimitry Andric    min_element(ForwardIterator first, ForwardIterator last);  // constexpr in C++14
5340b57cec5SDimitry Andric
5350b57cec5SDimitry Andrictemplate <class ForwardIterator, class Compare>
5360b57cec5SDimitry Andric    ForwardIterator
5370b57cec5SDimitry Andric    min_element(ForwardIterator first, ForwardIterator last, Compare comp);  // constexpr in C++14
5380b57cec5SDimitry Andric
5390b57cec5SDimitry Andrictemplate <class T>
5400b57cec5SDimitry Andric    const T&
5410b57cec5SDimitry Andric    min(const T& a, const T& b);  // constexpr in C++14
5420b57cec5SDimitry Andric
5430b57cec5SDimitry Andrictemplate <class T, class Compare>
5440b57cec5SDimitry Andric    const T&
5450b57cec5SDimitry Andric    min(const T& a, const T& b, Compare comp);  // constexpr in C++14
5460b57cec5SDimitry Andric
5470b57cec5SDimitry Andrictemplate<class T>
5480b57cec5SDimitry Andric    T
5490b57cec5SDimitry Andric    min(initializer_list<T> t);  // constexpr in C++14
5500b57cec5SDimitry Andric
5510b57cec5SDimitry Andrictemplate<class T, class Compare>
5520b57cec5SDimitry Andric    T
5530b57cec5SDimitry Andric    min(initializer_list<T> t, Compare comp);  // constexpr in C++14
5540b57cec5SDimitry Andric
5550b57cec5SDimitry Andrictemplate<class T>
5560b57cec5SDimitry Andric    constexpr const T& clamp( const T& v, const T& lo, const T& hi );               // C++17
5570b57cec5SDimitry Andric
5580b57cec5SDimitry Andrictemplate<class T, class Compare>
5590b57cec5SDimitry Andric    constexpr const T& clamp( const T& v, const T& lo, const T& hi, Compare comp ); // C++17
5600b57cec5SDimitry Andric
5610b57cec5SDimitry Andrictemplate <class ForwardIterator>
5620b57cec5SDimitry Andric    ForwardIterator
5630b57cec5SDimitry Andric    max_element(ForwardIterator first, ForwardIterator last);  // constexpr in C++14
5640b57cec5SDimitry Andric
5650b57cec5SDimitry Andrictemplate <class ForwardIterator, class Compare>
5660b57cec5SDimitry Andric    ForwardIterator
5670b57cec5SDimitry Andric    max_element(ForwardIterator first, ForwardIterator last, Compare comp);  // constexpr in C++14
5680b57cec5SDimitry Andric
5690b57cec5SDimitry Andrictemplate <class T>
5700b57cec5SDimitry Andric    const T&
5710b57cec5SDimitry Andric    max(const T& a, const T& b); // constexpr in C++14
5720b57cec5SDimitry Andric
5730b57cec5SDimitry Andrictemplate <class T, class Compare>
5740b57cec5SDimitry Andric    const T&
5750b57cec5SDimitry Andric    max(const T& a, const T& b, Compare comp);  // constexpr in C++14
5760b57cec5SDimitry Andric
5770b57cec5SDimitry Andrictemplate<class T>
5780b57cec5SDimitry Andric    T
5790b57cec5SDimitry Andric    max(initializer_list<T> t);  // constexpr in C++14
5800b57cec5SDimitry Andric
5810b57cec5SDimitry Andrictemplate<class T, class Compare>
5820b57cec5SDimitry Andric    T
5830b57cec5SDimitry Andric    max(initializer_list<T> t, Compare comp);  // constexpr in C++14
5840b57cec5SDimitry Andric
5850b57cec5SDimitry Andrictemplate<class ForwardIterator>
5860b57cec5SDimitry Andric    pair<ForwardIterator, ForwardIterator>
5870b57cec5SDimitry Andric    minmax_element(ForwardIterator first, ForwardIterator last);   // constexpr in C++14
5880b57cec5SDimitry Andric
5890b57cec5SDimitry Andrictemplate<class ForwardIterator, class Compare>
5900b57cec5SDimitry Andric    pair<ForwardIterator, ForwardIterator>
5910b57cec5SDimitry Andric    minmax_element(ForwardIterator first, ForwardIterator last, Compare comp);   // constexpr in C++14
5920b57cec5SDimitry Andric
5930b57cec5SDimitry Andrictemplate<class T>
5940b57cec5SDimitry Andric    pair<const T&, const T&>
5950b57cec5SDimitry Andric    minmax(const T& a, const T& b);  // constexpr in C++14
5960b57cec5SDimitry Andric
5970b57cec5SDimitry Andrictemplate<class T, class Compare>
5980b57cec5SDimitry Andric    pair<const T&, const T&>
5990b57cec5SDimitry Andric    minmax(const T& a, const T& b, Compare comp);  // constexpr in C++14
6000b57cec5SDimitry Andric
6010b57cec5SDimitry Andrictemplate<class T>
6020b57cec5SDimitry Andric    pair<T, T>
6030b57cec5SDimitry Andric    minmax(initializer_list<T> t);  // constexpr in C++14
6040b57cec5SDimitry Andric
6050b57cec5SDimitry Andrictemplate<class T, class Compare>
6060b57cec5SDimitry Andric    pair<T, T>
6070b57cec5SDimitry Andric    minmax(initializer_list<T> t, Compare comp);  // constexpr in C++14
6080b57cec5SDimitry Andric
6090b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2>
6100b57cec5SDimitry Andric    constexpr bool     // constexpr in C++20
6110b57cec5SDimitry Andric    lexicographical_compare(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2);
6120b57cec5SDimitry Andric
6130b57cec5SDimitry Andrictemplate <class InputIterator1, class InputIterator2, class Compare>
6140b57cec5SDimitry Andric    constexpr bool     // constexpr in C++20
6150b57cec5SDimitry Andric    lexicographical_compare(InputIterator1 first1, InputIterator1 last1,
6160b57cec5SDimitry Andric                            InputIterator2 first2, InputIterator2 last2, Compare comp);
6170b57cec5SDimitry Andric
6180b57cec5SDimitry Andrictemplate <class BidirectionalIterator>
6190b57cec5SDimitry Andric    bool
6200b57cec5SDimitry Andric    next_permutation(BidirectionalIterator first, BidirectionalIterator last);
6210b57cec5SDimitry Andric
6220b57cec5SDimitry Andrictemplate <class BidirectionalIterator, class Compare>
6230b57cec5SDimitry Andric    bool
6240b57cec5SDimitry Andric    next_permutation(BidirectionalIterator first, BidirectionalIterator last, Compare comp);
6250b57cec5SDimitry Andric
6260b57cec5SDimitry Andrictemplate <class BidirectionalIterator>
6270b57cec5SDimitry Andric    bool
6280b57cec5SDimitry Andric    prev_permutation(BidirectionalIterator first, BidirectionalIterator last);
6290b57cec5SDimitry Andric
6300b57cec5SDimitry Andrictemplate <class BidirectionalIterator, class Compare>
6310b57cec5SDimitry Andric    bool
6320b57cec5SDimitry Andric    prev_permutation(BidirectionalIterator first, BidirectionalIterator last, Compare comp);
6330b57cec5SDimitry Andric
6340b57cec5SDimitry Andric}  // std
6350b57cec5SDimitry Andric
6360b57cec5SDimitry Andric*/
6370b57cec5SDimitry Andric
6380b57cec5SDimitry Andric#include <__config>
6390b57cec5SDimitry Andric#include <initializer_list>
6400b57cec5SDimitry Andric#include <type_traits>
6410b57cec5SDimitry Andric#include <cstring>
6420b57cec5SDimitry Andric#include <utility> // needed to provide swap_ranges.
6430b57cec5SDimitry Andric#include <memory>
6440b57cec5SDimitry Andric#include <functional>
6450b57cec5SDimitry Andric#include <iterator>
6460b57cec5SDimitry Andric#include <cstddef>
6470b57cec5SDimitry Andric#include <bit>
6480b57cec5SDimitry Andric#include <version>
6490b57cec5SDimitry Andric
6500b57cec5SDimitry Andric#include <__debug>
6510b57cec5SDimitry Andric
6520b57cec5SDimitry Andric#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
6530b57cec5SDimitry Andric#pragma GCC system_header
6540b57cec5SDimitry Andric#endif
6550b57cec5SDimitry Andric
6560b57cec5SDimitry Andric_LIBCPP_PUSH_MACROS
6570b57cec5SDimitry Andric#include <__undef_macros>
6580b57cec5SDimitry Andric
6590b57cec5SDimitry Andric
6600b57cec5SDimitry Andric_LIBCPP_BEGIN_NAMESPACE_STD
6610b57cec5SDimitry Andric
6620b57cec5SDimitry Andric// I'd like to replace these with _VSTD::equal_to<void>, but can't because:
6630b57cec5SDimitry Andric//   * That only works with C++14 and later, and
6640b57cec5SDimitry Andric//   * We haven't included <functional> here.
6650b57cec5SDimitry Andrictemplate <class _T1, class _T2 = _T1>
6660b57cec5SDimitry Andricstruct __equal_to
6670b57cec5SDimitry Andric{
6680b57cec5SDimitry Andric    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 bool operator()(const _T1& __x, const _T1& __y) const {return __x == __y;}
6690b57cec5SDimitry Andric    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 bool operator()(const _T1& __x, const _T2& __y) const {return __x == __y;}
6700b57cec5SDimitry Andric    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 bool operator()(const _T2& __x, const _T1& __y) const {return __x == __y;}
6710b57cec5SDimitry Andric    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 bool operator()(const _T2& __x, const _T2& __y) const {return __x == __y;}
6720b57cec5SDimitry Andric};
6730b57cec5SDimitry Andric
6740b57cec5SDimitry Andrictemplate <class _T1>
6750b57cec5SDimitry Andricstruct __equal_to<_T1, _T1>
6760b57cec5SDimitry Andric{
6770b57cec5SDimitry Andric    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
6780b57cec5SDimitry Andric    bool operator()(const _T1& __x, const _T1& __y) const {return __x == __y;}
6790b57cec5SDimitry Andric};
6800b57cec5SDimitry Andric
6810b57cec5SDimitry Andrictemplate <class _T1>
6820b57cec5SDimitry Andricstruct __equal_to<const _T1, _T1>
6830b57cec5SDimitry Andric{
6840b57cec5SDimitry Andric    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
6850b57cec5SDimitry Andric    bool operator()(const _T1& __x, const _T1& __y) const {return __x == __y;}
6860b57cec5SDimitry Andric};
6870b57cec5SDimitry Andric
6880b57cec5SDimitry Andrictemplate <class _T1>
6890b57cec5SDimitry Andricstruct __equal_to<_T1, const _T1>
6900b57cec5SDimitry Andric{
6910b57cec5SDimitry Andric    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
6920b57cec5SDimitry Andric    bool operator()(const _T1& __x, const _T1& __y) const {return __x == __y;}
6930b57cec5SDimitry Andric};
6940b57cec5SDimitry Andric
6950b57cec5SDimitry Andrictemplate <class _T1, class _T2 = _T1>
6960b57cec5SDimitry Andricstruct __less
6970b57cec5SDimitry Andric{
6980b57cec5SDimitry Andric    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
6990b57cec5SDimitry Andric    bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
7000b57cec5SDimitry Andric
7010b57cec5SDimitry Andric    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
7020b57cec5SDimitry Andric    bool operator()(const _T1& __x, const _T2& __y) const {return __x < __y;}
7030b57cec5SDimitry Andric
7040b57cec5SDimitry Andric    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
7050b57cec5SDimitry Andric    bool operator()(const _T2& __x, const _T1& __y) const {return __x < __y;}
7060b57cec5SDimitry Andric
7070b57cec5SDimitry Andric    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
7080b57cec5SDimitry Andric    bool operator()(const _T2& __x, const _T2& __y) const {return __x < __y;}
7090b57cec5SDimitry Andric};
7100b57cec5SDimitry Andric
7110b57cec5SDimitry Andrictemplate <class _T1>
7120b57cec5SDimitry Andricstruct __less<_T1, _T1>
7130b57cec5SDimitry Andric{
7140b57cec5SDimitry Andric    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
7150b57cec5SDimitry Andric    bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
7160b57cec5SDimitry Andric};
7170b57cec5SDimitry Andric
7180b57cec5SDimitry Andrictemplate <class _T1>
7190b57cec5SDimitry Andricstruct __less<const _T1, _T1>
7200b57cec5SDimitry Andric{
7210b57cec5SDimitry Andric    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
7220b57cec5SDimitry Andric    bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
7230b57cec5SDimitry Andric};
7240b57cec5SDimitry Andric
7250b57cec5SDimitry Andrictemplate <class _T1>
7260b57cec5SDimitry Andricstruct __less<_T1, const _T1>
7270b57cec5SDimitry Andric{
7280b57cec5SDimitry Andric    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
7290b57cec5SDimitry Andric    bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
7300b57cec5SDimitry Andric};
7310b57cec5SDimitry Andric
7320b57cec5SDimitry Andrictemplate <class _Predicate>
7330b57cec5SDimitry Andricclass __invert // invert the sense of a comparison
7340b57cec5SDimitry Andric{
7350b57cec5SDimitry Andricprivate:
7360b57cec5SDimitry Andric    _Predicate __p_;
7370b57cec5SDimitry Andricpublic:
7380b57cec5SDimitry Andric    _LIBCPP_INLINE_VISIBILITY __invert() {}
7390b57cec5SDimitry Andric
7400b57cec5SDimitry Andric    _LIBCPP_INLINE_VISIBILITY
7410b57cec5SDimitry Andric    explicit __invert(_Predicate __p) : __p_(__p) {}
7420b57cec5SDimitry Andric
7430b57cec5SDimitry Andric    template <class _T1>
7440b57cec5SDimitry Andric    _LIBCPP_INLINE_VISIBILITY
7450b57cec5SDimitry Andric    bool operator()(const _T1& __x) {return !__p_(__x);}
7460b57cec5SDimitry Andric
7470b57cec5SDimitry Andric    template <class _T1, class _T2>
7480b57cec5SDimitry Andric    _LIBCPP_INLINE_VISIBILITY
7490b57cec5SDimitry Andric    bool operator()(const _T1& __x, const _T2& __y) {return __p_(__y, __x);}
7500b57cec5SDimitry Andric};
7510b57cec5SDimitry Andric
7520b57cec5SDimitry Andric// Perform division by two quickly for positive integers (llvm.org/PR39129)
7530b57cec5SDimitry Andric
7540b57cec5SDimitry Andrictemplate <typename _Integral>
7550b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
7560b57cec5SDimitry Andrictypename enable_if
7570b57cec5SDimitry Andric<
7580b57cec5SDimitry Andric    is_integral<_Integral>::value,
7590b57cec5SDimitry Andric    _Integral
7600b57cec5SDimitry Andric>::type
7610b57cec5SDimitry Andric__half_positive(_Integral __value)
7620b57cec5SDimitry Andric{
7630b57cec5SDimitry Andric    return static_cast<_Integral>(static_cast<typename make_unsigned<_Integral>::type>(__value) / 2);
7640b57cec5SDimitry Andric}
7650b57cec5SDimitry Andric
7660b57cec5SDimitry Andrictemplate <typename _Tp>
7670b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
7680b57cec5SDimitry Andrictypename enable_if
7690b57cec5SDimitry Andric<
7700b57cec5SDimitry Andric    !is_integral<_Tp>::value,
7710b57cec5SDimitry Andric    _Tp
7720b57cec5SDimitry Andric>::type
7730b57cec5SDimitry Andric__half_positive(_Tp __value)
7740b57cec5SDimitry Andric{
7750b57cec5SDimitry Andric    return __value / 2;
7760b57cec5SDimitry Andric}
7770b57cec5SDimitry Andric
7780b57cec5SDimitry Andric#ifdef _LIBCPP_DEBUG
7790b57cec5SDimitry Andric
7800b57cec5SDimitry Andrictemplate <class _Compare>
7810b57cec5SDimitry Andricstruct __debug_less
7820b57cec5SDimitry Andric{
7830b57cec5SDimitry Andric    _Compare &__comp_;
7840b57cec5SDimitry Andric    _LIBCPP_CONSTEXPR_AFTER_CXX17
7850b57cec5SDimitry Andric    __debug_less(_Compare& __c) : __comp_(__c) {}
7860b57cec5SDimitry Andric
7870b57cec5SDimitry Andric    template <class _Tp, class _Up>
7880b57cec5SDimitry Andric    _LIBCPP_CONSTEXPR_AFTER_CXX17
7890b57cec5SDimitry Andric    bool operator()(const _Tp& __x,  const _Up& __y)
7900b57cec5SDimitry Andric    {
7910b57cec5SDimitry Andric        bool __r = __comp_(__x, __y);
7920b57cec5SDimitry Andric        if (__r)
7930b57cec5SDimitry Andric            __do_compare_assert(0, __y, __x);
7940b57cec5SDimitry Andric        return __r;
7950b57cec5SDimitry Andric    }
7960b57cec5SDimitry Andric
7970b57cec5SDimitry Andric    template <class _Tp, class _Up>
7980b57cec5SDimitry Andric    _LIBCPP_CONSTEXPR_AFTER_CXX17
7990b57cec5SDimitry Andric    bool operator()(_Tp& __x,  _Up& __y)
8000b57cec5SDimitry Andric    {
8010b57cec5SDimitry Andric        bool __r = __comp_(__x, __y);
8020b57cec5SDimitry Andric        if (__r)
8030b57cec5SDimitry Andric            __do_compare_assert(0, __y, __x);
8040b57cec5SDimitry Andric        return __r;
8050b57cec5SDimitry Andric    }
8060b57cec5SDimitry Andric
8070b57cec5SDimitry Andric    template <class _LHS, class _RHS>
8080b57cec5SDimitry Andric    _LIBCPP_CONSTEXPR_AFTER_CXX17
8090b57cec5SDimitry Andric    inline _LIBCPP_INLINE_VISIBILITY
8100b57cec5SDimitry Andric    decltype((void)_VSTD::declval<_Compare&>()(
8110b57cec5SDimitry Andric        _VSTD::declval<_LHS &>(), _VSTD::declval<_RHS &>()))
8120b57cec5SDimitry Andric    __do_compare_assert(int, _LHS & __l, _RHS & __r) {
8130b57cec5SDimitry Andric        _LIBCPP_ASSERT(!__comp_(__l, __r),
8140b57cec5SDimitry Andric            "Comparator does not induce a strict weak ordering");
8150b57cec5SDimitry Andric    }
8160b57cec5SDimitry Andric
8170b57cec5SDimitry Andric    template <class _LHS, class _RHS>
8180b57cec5SDimitry Andric    _LIBCPP_CONSTEXPR_AFTER_CXX17
8190b57cec5SDimitry Andric    inline _LIBCPP_INLINE_VISIBILITY
8200b57cec5SDimitry Andric    void __do_compare_assert(long, _LHS &, _RHS &) {}
8210b57cec5SDimitry Andric};
8220b57cec5SDimitry Andric
8230b57cec5SDimitry Andric#endif // _LIBCPP_DEBUG
8240b57cec5SDimitry Andric
8250b57cec5SDimitry Andrictemplate <class _Comp>
8260b57cec5SDimitry Andricstruct __comp_ref_type {
8270b57cec5SDimitry Andric  // Pass the comparator by lvalue reference. Or in debug mode, using a
8280b57cec5SDimitry Andric  // debugging wrapper that stores a reference.
8290b57cec5SDimitry Andric#ifndef _LIBCPP_DEBUG
8300b57cec5SDimitry Andric  typedef typename add_lvalue_reference<_Comp>::type type;
8310b57cec5SDimitry Andric#else
8320b57cec5SDimitry Andric  typedef __debug_less<_Comp> type;
8330b57cec5SDimitry Andric#endif
8340b57cec5SDimitry Andric};
8350b57cec5SDimitry Andric
8360b57cec5SDimitry Andric// all_of
8370b57cec5SDimitry Andric
8380b57cec5SDimitry Andrictemplate <class _InputIterator, class _Predicate>
8390b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
8400b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
8410b57cec5SDimitry Andricbool
8420b57cec5SDimitry Andricall_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
8430b57cec5SDimitry Andric{
8440b57cec5SDimitry Andric    for (; __first != __last; ++__first)
8450b57cec5SDimitry Andric        if (!__pred(*__first))
8460b57cec5SDimitry Andric            return false;
8470b57cec5SDimitry Andric    return true;
8480b57cec5SDimitry Andric}
8490b57cec5SDimitry Andric
8500b57cec5SDimitry Andric// any_of
8510b57cec5SDimitry Andric
8520b57cec5SDimitry Andrictemplate <class _InputIterator, class _Predicate>
8530b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
8540b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
8550b57cec5SDimitry Andricbool
8560b57cec5SDimitry Andricany_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
8570b57cec5SDimitry Andric{
8580b57cec5SDimitry Andric    for (; __first != __last; ++__first)
8590b57cec5SDimitry Andric        if (__pred(*__first))
8600b57cec5SDimitry Andric            return true;
8610b57cec5SDimitry Andric    return false;
8620b57cec5SDimitry Andric}
8630b57cec5SDimitry Andric
8640b57cec5SDimitry Andric// none_of
8650b57cec5SDimitry Andric
8660b57cec5SDimitry Andrictemplate <class _InputIterator, class _Predicate>
8670b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
8680b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
8690b57cec5SDimitry Andricbool
8700b57cec5SDimitry Andricnone_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
8710b57cec5SDimitry Andric{
8720b57cec5SDimitry Andric    for (; __first != __last; ++__first)
8730b57cec5SDimitry Andric        if (__pred(*__first))
8740b57cec5SDimitry Andric            return false;
8750b57cec5SDimitry Andric    return true;
8760b57cec5SDimitry Andric}
8770b57cec5SDimitry Andric
8780b57cec5SDimitry Andric// for_each
8790b57cec5SDimitry Andric
8800b57cec5SDimitry Andrictemplate <class _InputIterator, class _Function>
8810b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
8820b57cec5SDimitry Andric_Function
8830b57cec5SDimitry Andricfor_each(_InputIterator __first, _InputIterator __last, _Function __f)
8840b57cec5SDimitry Andric{
8850b57cec5SDimitry Andric    for (; __first != __last; ++__first)
8860b57cec5SDimitry Andric        __f(*__first);
8870b57cec5SDimitry Andric    return __f;
8880b57cec5SDimitry Andric}
8890b57cec5SDimitry Andric
8900b57cec5SDimitry Andric#if _LIBCPP_STD_VER > 14
8910b57cec5SDimitry Andric// for_each_n
8920b57cec5SDimitry Andric
8930b57cec5SDimitry Andrictemplate <class _InputIterator, class _Size, class _Function>
8940b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
8950b57cec5SDimitry Andric_InputIterator
8960b57cec5SDimitry Andricfor_each_n(_InputIterator __first, _Size __orig_n, _Function __f)
8970b57cec5SDimitry Andric{
8980b57cec5SDimitry Andric    typedef decltype(__convert_to_integral(__orig_n)) _IntegralSize;
8990b57cec5SDimitry Andric    _IntegralSize __n = __orig_n;
9000b57cec5SDimitry Andric    while (__n > 0)
9010b57cec5SDimitry Andric    {
9020b57cec5SDimitry Andric         __f(*__first);
9030b57cec5SDimitry Andric         ++__first;
9040b57cec5SDimitry Andric         --__n;
9050b57cec5SDimitry Andric    }
9060b57cec5SDimitry Andric    return __first;
9070b57cec5SDimitry Andric}
9080b57cec5SDimitry Andric#endif
9090b57cec5SDimitry Andric
9100b57cec5SDimitry Andric// find
9110b57cec5SDimitry Andric
9120b57cec5SDimitry Andrictemplate <class _InputIterator, class _Tp>
9130b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
9140b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
9150b57cec5SDimitry Andric_InputIterator
9160b57cec5SDimitry Andricfind(_InputIterator __first, _InputIterator __last, const _Tp& __value_)
9170b57cec5SDimitry Andric{
9180b57cec5SDimitry Andric    for (; __first != __last; ++__first)
9190b57cec5SDimitry Andric        if (*__first == __value_)
9200b57cec5SDimitry Andric            break;
9210b57cec5SDimitry Andric    return __first;
9220b57cec5SDimitry Andric}
9230b57cec5SDimitry Andric
9240b57cec5SDimitry Andric// find_if
9250b57cec5SDimitry Andric
9260b57cec5SDimitry Andrictemplate <class _InputIterator, class _Predicate>
9270b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
9280b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
9290b57cec5SDimitry Andric_InputIterator
9300b57cec5SDimitry Andricfind_if(_InputIterator __first, _InputIterator __last, _Predicate __pred)
9310b57cec5SDimitry Andric{
9320b57cec5SDimitry Andric    for (; __first != __last; ++__first)
9330b57cec5SDimitry Andric        if (__pred(*__first))
9340b57cec5SDimitry Andric            break;
9350b57cec5SDimitry Andric    return __first;
9360b57cec5SDimitry Andric}
9370b57cec5SDimitry Andric
9380b57cec5SDimitry Andric// find_if_not
9390b57cec5SDimitry Andric
9400b57cec5SDimitry Andrictemplate<class _InputIterator, class _Predicate>
9410b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
9420b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
9430b57cec5SDimitry Andric_InputIterator
9440b57cec5SDimitry Andricfind_if_not(_InputIterator __first, _InputIterator __last, _Predicate __pred)
9450b57cec5SDimitry Andric{
9460b57cec5SDimitry Andric    for (; __first != __last; ++__first)
9470b57cec5SDimitry Andric        if (!__pred(*__first))
9480b57cec5SDimitry Andric            break;
9490b57cec5SDimitry Andric    return __first;
9500b57cec5SDimitry Andric}
9510b57cec5SDimitry Andric
9520b57cec5SDimitry Andric// find_end
9530b57cec5SDimitry Andric
9540b57cec5SDimitry Andrictemplate <class _BinaryPredicate, class _ForwardIterator1, class _ForwardIterator2>
9550b57cec5SDimitry Andric_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator1
9560b57cec5SDimitry Andric__find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
9570b57cec5SDimitry Andric           _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred,
9580b57cec5SDimitry Andric           forward_iterator_tag, forward_iterator_tag)
9590b57cec5SDimitry Andric{
9600b57cec5SDimitry Andric    // modeled after search algorithm
9610b57cec5SDimitry Andric    _ForwardIterator1 __r = __last1;  // __last1 is the "default" answer
9620b57cec5SDimitry Andric    if (__first2 == __last2)
9630b57cec5SDimitry Andric        return __r;
9640b57cec5SDimitry Andric    while (true)
9650b57cec5SDimitry Andric    {
9660b57cec5SDimitry Andric        while (true)
9670b57cec5SDimitry Andric        {
9680b57cec5SDimitry Andric            if (__first1 == __last1)         // if source exhausted return last correct answer
9690b57cec5SDimitry Andric                return __r;                  //    (or __last1 if never found)
9700b57cec5SDimitry Andric            if (__pred(*__first1, *__first2))
9710b57cec5SDimitry Andric                break;
9720b57cec5SDimitry Andric            ++__first1;
9730b57cec5SDimitry Andric        }
9740b57cec5SDimitry Andric        // *__first1 matches *__first2, now match elements after here
9750b57cec5SDimitry Andric        _ForwardIterator1 __m1 = __first1;
9760b57cec5SDimitry Andric        _ForwardIterator2 __m2 = __first2;
9770b57cec5SDimitry Andric        while (true)
9780b57cec5SDimitry Andric        {
9790b57cec5SDimitry Andric            if (++__m2 == __last2)
9800b57cec5SDimitry Andric            {                         // Pattern exhaused, record answer and search for another one
9810b57cec5SDimitry Andric                __r = __first1;
9820b57cec5SDimitry Andric                ++__first1;
9830b57cec5SDimitry Andric                break;
9840b57cec5SDimitry Andric            }
9850b57cec5SDimitry Andric            if (++__m1 == __last1)     // Source exhausted, return last answer
9860b57cec5SDimitry Andric                return __r;
9870b57cec5SDimitry Andric            if (!__pred(*__m1, *__m2))  // mismatch, restart with a new __first
9880b57cec5SDimitry Andric            {
9890b57cec5SDimitry Andric                ++__first1;
9900b57cec5SDimitry Andric                break;
9910b57cec5SDimitry Andric            }  // else there is a match, check next elements
9920b57cec5SDimitry Andric        }
9930b57cec5SDimitry Andric    }
9940b57cec5SDimitry Andric}
9950b57cec5SDimitry Andric
9960b57cec5SDimitry Andrictemplate <class _BinaryPredicate, class _BidirectionalIterator1, class _BidirectionalIterator2>
9970b57cec5SDimitry Andric_LIBCPP_CONSTEXPR_AFTER_CXX17 _BidirectionalIterator1
9980b57cec5SDimitry Andric__find_end(_BidirectionalIterator1 __first1, _BidirectionalIterator1 __last1,
9990b57cec5SDimitry Andric           _BidirectionalIterator2 __first2, _BidirectionalIterator2 __last2, _BinaryPredicate __pred,
10000b57cec5SDimitry Andric           bidirectional_iterator_tag, bidirectional_iterator_tag)
10010b57cec5SDimitry Andric{
10020b57cec5SDimitry Andric    // modeled after search algorithm (in reverse)
10030b57cec5SDimitry Andric    if (__first2 == __last2)
10040b57cec5SDimitry Andric        return __last1;  // Everything matches an empty sequence
10050b57cec5SDimitry Andric    _BidirectionalIterator1 __l1 = __last1;
10060b57cec5SDimitry Andric    _BidirectionalIterator2 __l2 = __last2;
10070b57cec5SDimitry Andric    --__l2;
10080b57cec5SDimitry Andric    while (true)
10090b57cec5SDimitry Andric    {
10100b57cec5SDimitry Andric        // Find last element in sequence 1 that matchs *(__last2-1), with a mininum of loop checks
10110b57cec5SDimitry Andric        while (true)
10120b57cec5SDimitry Andric        {
10130b57cec5SDimitry Andric            if (__first1 == __l1)  // return __last1 if no element matches *__first2
10140b57cec5SDimitry Andric                return __last1;
10150b57cec5SDimitry Andric            if (__pred(*--__l1, *__l2))
10160b57cec5SDimitry Andric                break;
10170b57cec5SDimitry Andric        }
10180b57cec5SDimitry Andric        // *__l1 matches *__l2, now match elements before here
10190b57cec5SDimitry Andric        _BidirectionalIterator1 __m1 = __l1;
10200b57cec5SDimitry Andric        _BidirectionalIterator2 __m2 = __l2;
10210b57cec5SDimitry Andric        while (true)
10220b57cec5SDimitry Andric        {
10230b57cec5SDimitry Andric            if (__m2 == __first2)  // If pattern exhausted, __m1 is the answer (works for 1 element pattern)
10240b57cec5SDimitry Andric                return __m1;
10250b57cec5SDimitry Andric            if (__m1 == __first1)  // Otherwise if source exhaused, pattern not found
10260b57cec5SDimitry Andric                return __last1;
10270b57cec5SDimitry Andric            if (!__pred(*--__m1, *--__m2))  // if there is a mismatch, restart with a new __l1
10280b57cec5SDimitry Andric            {
10290b57cec5SDimitry Andric                break;
10300b57cec5SDimitry Andric            }  // else there is a match, check next elements
10310b57cec5SDimitry Andric        }
10320b57cec5SDimitry Andric    }
10330b57cec5SDimitry Andric}
10340b57cec5SDimitry Andric
10350b57cec5SDimitry Andrictemplate <class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
10360b57cec5SDimitry Andric_LIBCPP_CONSTEXPR_AFTER_CXX11 _RandomAccessIterator1
10370b57cec5SDimitry Andric__find_end(_RandomAccessIterator1 __first1, _RandomAccessIterator1 __last1,
10380b57cec5SDimitry Andric           _RandomAccessIterator2 __first2, _RandomAccessIterator2 __last2, _BinaryPredicate __pred,
10390b57cec5SDimitry Andric           random_access_iterator_tag, random_access_iterator_tag)
10400b57cec5SDimitry Andric{
10410b57cec5SDimitry Andric    // Take advantage of knowing source and pattern lengths.  Stop short when source is smaller than pattern
10420b57cec5SDimitry Andric    typename iterator_traits<_RandomAccessIterator2>::difference_type __len2 = __last2 - __first2;
10430b57cec5SDimitry Andric    if (__len2 == 0)
10440b57cec5SDimitry Andric        return __last1;
10450b57cec5SDimitry Andric    typename iterator_traits<_RandomAccessIterator1>::difference_type __len1 = __last1 - __first1;
10460b57cec5SDimitry Andric    if (__len1 < __len2)
10470b57cec5SDimitry Andric        return __last1;
10480b57cec5SDimitry Andric    const _RandomAccessIterator1 __s = __first1 + (__len2 - 1);  // End of pattern match can't go before here
10490b57cec5SDimitry Andric    _RandomAccessIterator1 __l1 = __last1;
10500b57cec5SDimitry Andric    _RandomAccessIterator2 __l2 = __last2;
10510b57cec5SDimitry Andric    --__l2;
10520b57cec5SDimitry Andric    while (true)
10530b57cec5SDimitry Andric    {
10540b57cec5SDimitry Andric        while (true)
10550b57cec5SDimitry Andric        {
10560b57cec5SDimitry Andric            if (__s == __l1)
10570b57cec5SDimitry Andric                return __last1;
10580b57cec5SDimitry Andric            if (__pred(*--__l1, *__l2))
10590b57cec5SDimitry Andric                break;
10600b57cec5SDimitry Andric        }
10610b57cec5SDimitry Andric        _RandomAccessIterator1 __m1 = __l1;
10620b57cec5SDimitry Andric        _RandomAccessIterator2 __m2 = __l2;
10630b57cec5SDimitry Andric        while (true)
10640b57cec5SDimitry Andric        {
10650b57cec5SDimitry Andric            if (__m2 == __first2)
10660b57cec5SDimitry Andric                return __m1;
10670b57cec5SDimitry Andric                                 // no need to check range on __m1 because __s guarantees we have enough source
10680b57cec5SDimitry Andric            if (!__pred(*--__m1, *--__m2))
10690b57cec5SDimitry Andric            {
10700b57cec5SDimitry Andric                break;
10710b57cec5SDimitry Andric            }
10720b57cec5SDimitry Andric        }
10730b57cec5SDimitry Andric    }
10740b57cec5SDimitry Andric}
10750b57cec5SDimitry Andric
10760b57cec5SDimitry Andrictemplate <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
10770b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
10780b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
10790b57cec5SDimitry Andric_ForwardIterator1
10800b57cec5SDimitry Andricfind_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
10810b57cec5SDimitry Andric         _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred)
10820b57cec5SDimitry Andric{
10830b57cec5SDimitry Andric    return _VSTD::__find_end<typename add_lvalue_reference<_BinaryPredicate>::type>
10840b57cec5SDimitry Andric                         (__first1, __last1, __first2, __last2, __pred,
10850b57cec5SDimitry Andric                          typename iterator_traits<_ForwardIterator1>::iterator_category(),
10860b57cec5SDimitry Andric                          typename iterator_traits<_ForwardIterator2>::iterator_category());
10870b57cec5SDimitry Andric}
10880b57cec5SDimitry Andric
10890b57cec5SDimitry Andrictemplate <class _ForwardIterator1, class _ForwardIterator2>
10900b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
10910b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
10920b57cec5SDimitry Andric_ForwardIterator1
10930b57cec5SDimitry Andricfind_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
10940b57cec5SDimitry Andric         _ForwardIterator2 __first2, _ForwardIterator2 __last2)
10950b57cec5SDimitry Andric{
10960b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
10970b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
10980b57cec5SDimitry Andric    return _VSTD::find_end(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
10990b57cec5SDimitry Andric}
11000b57cec5SDimitry Andric
11010b57cec5SDimitry Andric// find_first_of
11020b57cec5SDimitry Andric
11030b57cec5SDimitry Andrictemplate <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
11040b57cec5SDimitry Andric_LIBCPP_CONSTEXPR_AFTER_CXX11 _ForwardIterator1
11050b57cec5SDimitry Andric__find_first_of_ce(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
11060b57cec5SDimitry Andric              _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred)
11070b57cec5SDimitry Andric{
11080b57cec5SDimitry Andric    for (; __first1 != __last1; ++__first1)
11090b57cec5SDimitry Andric        for (_ForwardIterator2 __j = __first2; __j != __last2; ++__j)
11100b57cec5SDimitry Andric            if (__pred(*__first1, *__j))
11110b57cec5SDimitry Andric                return __first1;
11120b57cec5SDimitry Andric    return __last1;
11130b57cec5SDimitry Andric}
11140b57cec5SDimitry Andric
11150b57cec5SDimitry Andric
11160b57cec5SDimitry Andrictemplate <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
11170b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
11180b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
11190b57cec5SDimitry Andric_ForwardIterator1
11200b57cec5SDimitry Andricfind_first_of(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
11210b57cec5SDimitry Andric              _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred)
11220b57cec5SDimitry Andric{
11230b57cec5SDimitry Andric    return _VSTD::__find_first_of_ce(__first1, __last1, __first2, __last2, __pred);
11240b57cec5SDimitry Andric}
11250b57cec5SDimitry Andric
11260b57cec5SDimitry Andrictemplate <class _ForwardIterator1, class _ForwardIterator2>
11270b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
11280b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
11290b57cec5SDimitry Andric_ForwardIterator1
11300b57cec5SDimitry Andricfind_first_of(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
11310b57cec5SDimitry Andric              _ForwardIterator2 __first2, _ForwardIterator2 __last2)
11320b57cec5SDimitry Andric{
11330b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
11340b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
11350b57cec5SDimitry Andric    return _VSTD::__find_first_of_ce(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
11360b57cec5SDimitry Andric}
11370b57cec5SDimitry Andric
11380b57cec5SDimitry Andric// adjacent_find
11390b57cec5SDimitry Andric
11400b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _BinaryPredicate>
11410b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
11420b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
11430b57cec5SDimitry Andric_ForwardIterator
11440b57cec5SDimitry Andricadjacent_find(_ForwardIterator __first, _ForwardIterator __last, _BinaryPredicate __pred)
11450b57cec5SDimitry Andric{
11460b57cec5SDimitry Andric    if (__first != __last)
11470b57cec5SDimitry Andric    {
11480b57cec5SDimitry Andric        _ForwardIterator __i = __first;
11490b57cec5SDimitry Andric        while (++__i != __last)
11500b57cec5SDimitry Andric        {
11510b57cec5SDimitry Andric            if (__pred(*__first, *__i))
11520b57cec5SDimitry Andric                return __first;
11530b57cec5SDimitry Andric            __first = __i;
11540b57cec5SDimitry Andric        }
11550b57cec5SDimitry Andric    }
11560b57cec5SDimitry Andric    return __last;
11570b57cec5SDimitry Andric}
11580b57cec5SDimitry Andric
11590b57cec5SDimitry Andrictemplate <class _ForwardIterator>
11600b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
11610b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
11620b57cec5SDimitry Andric_ForwardIterator
11630b57cec5SDimitry Andricadjacent_find(_ForwardIterator __first, _ForwardIterator __last)
11640b57cec5SDimitry Andric{
11650b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator>::value_type __v;
11660b57cec5SDimitry Andric    return _VSTD::adjacent_find(__first, __last, __equal_to<__v>());
11670b57cec5SDimitry Andric}
11680b57cec5SDimitry Andric
11690b57cec5SDimitry Andric// count
11700b57cec5SDimitry Andric
11710b57cec5SDimitry Andrictemplate <class _InputIterator, class _Tp>
11720b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
11730b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
11740b57cec5SDimitry Andrictypename iterator_traits<_InputIterator>::difference_type
11750b57cec5SDimitry Andriccount(_InputIterator __first, _InputIterator __last, const _Tp& __value_)
11760b57cec5SDimitry Andric{
11770b57cec5SDimitry Andric    typename iterator_traits<_InputIterator>::difference_type __r(0);
11780b57cec5SDimitry Andric    for (; __first != __last; ++__first)
11790b57cec5SDimitry Andric        if (*__first == __value_)
11800b57cec5SDimitry Andric            ++__r;
11810b57cec5SDimitry Andric    return __r;
11820b57cec5SDimitry Andric}
11830b57cec5SDimitry Andric
11840b57cec5SDimitry Andric// count_if
11850b57cec5SDimitry Andric
11860b57cec5SDimitry Andrictemplate <class _InputIterator, class _Predicate>
11870b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
11880b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
11890b57cec5SDimitry Andrictypename iterator_traits<_InputIterator>::difference_type
11900b57cec5SDimitry Andriccount_if(_InputIterator __first, _InputIterator __last, _Predicate __pred)
11910b57cec5SDimitry Andric{
11920b57cec5SDimitry Andric    typename iterator_traits<_InputIterator>::difference_type __r(0);
11930b57cec5SDimitry Andric    for (; __first != __last; ++__first)
11940b57cec5SDimitry Andric        if (__pred(*__first))
11950b57cec5SDimitry Andric            ++__r;
11960b57cec5SDimitry Andric    return __r;
11970b57cec5SDimitry Andric}
11980b57cec5SDimitry Andric
11990b57cec5SDimitry Andric// mismatch
12000b57cec5SDimitry Andric
12010b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
12020b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
12030b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12040b57cec5SDimitry Andricpair<_InputIterator1, _InputIterator2>
12050b57cec5SDimitry Andricmismatch(_InputIterator1 __first1, _InputIterator1 __last1,
12060b57cec5SDimitry Andric         _InputIterator2 __first2, _BinaryPredicate __pred)
12070b57cec5SDimitry Andric{
12080b57cec5SDimitry Andric    for (; __first1 != __last1; ++__first1, (void) ++__first2)
12090b57cec5SDimitry Andric        if (!__pred(*__first1, *__first2))
12100b57cec5SDimitry Andric            break;
12110b57cec5SDimitry Andric    return pair<_InputIterator1, _InputIterator2>(__first1, __first2);
12120b57cec5SDimitry Andric}
12130b57cec5SDimitry Andric
12140b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2>
12150b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
12160b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12170b57cec5SDimitry Andricpair<_InputIterator1, _InputIterator2>
12180b57cec5SDimitry Andricmismatch(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2)
12190b57cec5SDimitry Andric{
12200b57cec5SDimitry Andric    typedef typename iterator_traits<_InputIterator1>::value_type __v1;
12210b57cec5SDimitry Andric    typedef typename iterator_traits<_InputIterator2>::value_type __v2;
12220b57cec5SDimitry Andric    return _VSTD::mismatch(__first1, __last1, __first2, __equal_to<__v1, __v2>());
12230b57cec5SDimitry Andric}
12240b57cec5SDimitry Andric
12250b57cec5SDimitry Andric#if _LIBCPP_STD_VER > 11
12260b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
12270b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
12280b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12290b57cec5SDimitry Andricpair<_InputIterator1, _InputIterator2>
12300b57cec5SDimitry Andricmismatch(_InputIterator1 __first1, _InputIterator1 __last1,
12310b57cec5SDimitry Andric         _InputIterator2 __first2, _InputIterator2 __last2,
12320b57cec5SDimitry Andric         _BinaryPredicate __pred)
12330b57cec5SDimitry Andric{
12340b57cec5SDimitry Andric    for (; __first1 != __last1 && __first2 != __last2; ++__first1, (void) ++__first2)
12350b57cec5SDimitry Andric        if (!__pred(*__first1, *__first2))
12360b57cec5SDimitry Andric            break;
12370b57cec5SDimitry Andric    return pair<_InputIterator1, _InputIterator2>(__first1, __first2);
12380b57cec5SDimitry Andric}
12390b57cec5SDimitry Andric
12400b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2>
12410b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
12420b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12430b57cec5SDimitry Andricpair<_InputIterator1, _InputIterator2>
12440b57cec5SDimitry Andricmismatch(_InputIterator1 __first1, _InputIterator1 __last1,
12450b57cec5SDimitry Andric         _InputIterator2 __first2, _InputIterator2 __last2)
12460b57cec5SDimitry Andric{
12470b57cec5SDimitry Andric    typedef typename iterator_traits<_InputIterator1>::value_type __v1;
12480b57cec5SDimitry Andric    typedef typename iterator_traits<_InputIterator2>::value_type __v2;
12490b57cec5SDimitry Andric    return _VSTD::mismatch(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
12500b57cec5SDimitry Andric}
12510b57cec5SDimitry Andric#endif
12520b57cec5SDimitry Andric
12530b57cec5SDimitry Andric// equal
12540b57cec5SDimitry Andric
12550b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
12560b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
12570b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12580b57cec5SDimitry Andricbool
12590b57cec5SDimitry Andricequal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _BinaryPredicate __pred)
12600b57cec5SDimitry Andric{
12610b57cec5SDimitry Andric    for (; __first1 != __last1; ++__first1, (void) ++__first2)
12620b57cec5SDimitry Andric        if (!__pred(*__first1, *__first2))
12630b57cec5SDimitry Andric            return false;
12640b57cec5SDimitry Andric    return true;
12650b57cec5SDimitry Andric}
12660b57cec5SDimitry Andric
12670b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2>
12680b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
12690b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12700b57cec5SDimitry Andricbool
12710b57cec5SDimitry Andricequal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2)
12720b57cec5SDimitry Andric{
12730b57cec5SDimitry Andric    typedef typename iterator_traits<_InputIterator1>::value_type __v1;
12740b57cec5SDimitry Andric    typedef typename iterator_traits<_InputIterator2>::value_type __v2;
12750b57cec5SDimitry Andric    return _VSTD::equal(__first1, __last1, __first2, __equal_to<__v1, __v2>());
12760b57cec5SDimitry Andric}
12770b57cec5SDimitry Andric
12780b57cec5SDimitry Andric#if _LIBCPP_STD_VER > 11
12790b57cec5SDimitry Andrictemplate <class _BinaryPredicate, class _InputIterator1, class _InputIterator2>
12800b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12810b57cec5SDimitry Andricbool
12820b57cec5SDimitry Andric__equal(_InputIterator1 __first1, _InputIterator1 __last1,
12830b57cec5SDimitry Andric        _InputIterator2 __first2, _InputIterator2 __last2, _BinaryPredicate __pred,
12840b57cec5SDimitry Andric        input_iterator_tag, input_iterator_tag )
12850b57cec5SDimitry Andric{
12860b57cec5SDimitry Andric    for (; __first1 != __last1 && __first2 != __last2; ++__first1, (void) ++__first2)
12870b57cec5SDimitry Andric        if (!__pred(*__first1, *__first2))
12880b57cec5SDimitry Andric            return false;
12890b57cec5SDimitry Andric    return __first1 == __last1 && __first2 == __last2;
12900b57cec5SDimitry Andric}
12910b57cec5SDimitry Andric
12920b57cec5SDimitry Andrictemplate <class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
12930b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12940b57cec5SDimitry Andricbool
12950b57cec5SDimitry Andric__equal(_RandomAccessIterator1 __first1, _RandomAccessIterator1 __last1,
12960b57cec5SDimitry Andric        _RandomAccessIterator2 __first2, _RandomAccessIterator2 __last2, _BinaryPredicate __pred,
12970b57cec5SDimitry Andric      random_access_iterator_tag, random_access_iterator_tag )
12980b57cec5SDimitry Andric{
12990b57cec5SDimitry Andric    if ( _VSTD::distance(__first1, __last1) != _VSTD::distance(__first2, __last2))
13000b57cec5SDimitry Andric        return false;
13010b57cec5SDimitry Andric    return _VSTD::equal<_RandomAccessIterator1, _RandomAccessIterator2,
13020b57cec5SDimitry Andric                        typename add_lvalue_reference<_BinaryPredicate>::type>
13030b57cec5SDimitry Andric                       (__first1, __last1, __first2, __pred );
13040b57cec5SDimitry Andric}
13050b57cec5SDimitry Andric
13060b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
13070b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
13080b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
13090b57cec5SDimitry Andricbool
13100b57cec5SDimitry Andricequal(_InputIterator1 __first1, _InputIterator1 __last1,
13110b57cec5SDimitry Andric      _InputIterator2 __first2, _InputIterator2 __last2, _BinaryPredicate __pred )
13120b57cec5SDimitry Andric{
13130b57cec5SDimitry Andric    return _VSTD::__equal<typename add_lvalue_reference<_BinaryPredicate>::type>
13140b57cec5SDimitry Andric       (__first1, __last1, __first2, __last2, __pred,
13150b57cec5SDimitry Andric        typename iterator_traits<_InputIterator1>::iterator_category(),
13160b57cec5SDimitry Andric        typename iterator_traits<_InputIterator2>::iterator_category());
13170b57cec5SDimitry Andric}
13180b57cec5SDimitry Andric
13190b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2>
13200b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
13210b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
13220b57cec5SDimitry Andricbool
13230b57cec5SDimitry Andricequal(_InputIterator1 __first1, _InputIterator1 __last1,
13240b57cec5SDimitry Andric      _InputIterator2 __first2, _InputIterator2 __last2)
13250b57cec5SDimitry Andric{
13260b57cec5SDimitry Andric    typedef typename iterator_traits<_InputIterator1>::value_type __v1;
13270b57cec5SDimitry Andric    typedef typename iterator_traits<_InputIterator2>::value_type __v2;
13280b57cec5SDimitry Andric    return _VSTD::__equal(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>(),
13290b57cec5SDimitry Andric        typename iterator_traits<_InputIterator1>::iterator_category(),
13300b57cec5SDimitry Andric        typename iterator_traits<_InputIterator2>::iterator_category());
13310b57cec5SDimitry Andric}
13320b57cec5SDimitry Andric#endif
13330b57cec5SDimitry Andric
13340b57cec5SDimitry Andric// is_permutation
13350b57cec5SDimitry Andric
13360b57cec5SDimitry Andrictemplate<class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
13370b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 bool
13380b57cec5SDimitry Andricis_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
13390b57cec5SDimitry Andric               _ForwardIterator2 __first2, _BinaryPredicate __pred)
13400b57cec5SDimitry Andric{
13410b57cec5SDimitry Andric//  shorten sequences as much as possible by lopping of any equal prefix
13420b57cec5SDimitry Andric    for (; __first1 != __last1; ++__first1, (void) ++__first2)
13430b57cec5SDimitry Andric        if (!__pred(*__first1, *__first2))
13440b57cec5SDimitry Andric            break;
13450b57cec5SDimitry Andric    if (__first1 == __last1)
13460b57cec5SDimitry Andric        return true;
13470b57cec5SDimitry Andric
13480b57cec5SDimitry Andric//  __first1 != __last1 && *__first1 != *__first2
13490b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator1>::difference_type _D1;
13500b57cec5SDimitry Andric    _D1 __l1 = _VSTD::distance(__first1, __last1);
13510b57cec5SDimitry Andric    if (__l1 == _D1(1))
13520b57cec5SDimitry Andric        return false;
13530b57cec5SDimitry Andric    _ForwardIterator2 __last2 = _VSTD::next(__first2, __l1);
13540b57cec5SDimitry Andric    // For each element in [f1, l1) see if there are the same number of
13550b57cec5SDimitry Andric    //    equal elements in [f2, l2)
13560b57cec5SDimitry Andric    for (_ForwardIterator1 __i = __first1; __i != __last1; ++__i)
13570b57cec5SDimitry Andric    {
13580b57cec5SDimitry Andric    //  Have we already counted the number of *__i in [f1, l1)?
13590b57cec5SDimitry Andric        _ForwardIterator1 __match = __first1;
13600b57cec5SDimitry Andric        for (; __match != __i; ++__match)
13610b57cec5SDimitry Andric            if (__pred(*__match, *__i))
13620b57cec5SDimitry Andric                break;
13630b57cec5SDimitry Andric        if (__match == __i) {
13640b57cec5SDimitry Andric            // Count number of *__i in [f2, l2)
13650b57cec5SDimitry Andric            _D1 __c2 = 0;
13660b57cec5SDimitry Andric            for (_ForwardIterator2 __j = __first2; __j != __last2; ++__j)
13670b57cec5SDimitry Andric                if (__pred(*__i, *__j))
13680b57cec5SDimitry Andric                    ++__c2;
13690b57cec5SDimitry Andric            if (__c2 == 0)
13700b57cec5SDimitry Andric                return false;
13710b57cec5SDimitry Andric            // Count number of *__i in [__i, l1) (we can start with 1)
13720b57cec5SDimitry Andric            _D1 __c1 = 1;
13730b57cec5SDimitry Andric            for (_ForwardIterator1 __j = _VSTD::next(__i); __j != __last1; ++__j)
13740b57cec5SDimitry Andric                if (__pred(*__i, *__j))
13750b57cec5SDimitry Andric                    ++__c1;
13760b57cec5SDimitry Andric            if (__c1 != __c2)
13770b57cec5SDimitry Andric                return false;
13780b57cec5SDimitry Andric        }
13790b57cec5SDimitry Andric    }
13800b57cec5SDimitry Andric    return true;
13810b57cec5SDimitry Andric}
13820b57cec5SDimitry Andric
13830b57cec5SDimitry Andrictemplate<class _ForwardIterator1, class _ForwardIterator2>
13840b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
13850b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
13860b57cec5SDimitry Andricbool
13870b57cec5SDimitry Andricis_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
13880b57cec5SDimitry Andric               _ForwardIterator2 __first2)
13890b57cec5SDimitry Andric{
13900b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
13910b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
13920b57cec5SDimitry Andric    return _VSTD::is_permutation(__first1, __last1, __first2, __equal_to<__v1, __v2>());
13930b57cec5SDimitry Andric}
13940b57cec5SDimitry Andric
13950b57cec5SDimitry Andric#if _LIBCPP_STD_VER > 11
13960b57cec5SDimitry Andrictemplate<class _BinaryPredicate, class _ForwardIterator1, class _ForwardIterator2>
13970b57cec5SDimitry Andric_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
13980b57cec5SDimitry Andric__is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
13990b57cec5SDimitry Andric                 _ForwardIterator2 __first2, _ForwardIterator2 __last2,
14000b57cec5SDimitry Andric                 _BinaryPredicate __pred,
14010b57cec5SDimitry Andric                 forward_iterator_tag, forward_iterator_tag )
14020b57cec5SDimitry Andric{
14030b57cec5SDimitry Andric//  shorten sequences as much as possible by lopping of any equal prefix
14040b57cec5SDimitry Andric    for (; __first1 != __last1 && __first2 != __last2; ++__first1, (void) ++__first2)
14050b57cec5SDimitry Andric        if (!__pred(*__first1, *__first2))
14060b57cec5SDimitry Andric            break;
14070b57cec5SDimitry Andric    if (__first1 == __last1)
14080b57cec5SDimitry Andric        return __first2 == __last2;
14090b57cec5SDimitry Andric    else if (__first2 == __last2)
14100b57cec5SDimitry Andric        return false;
14110b57cec5SDimitry Andric
14120b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator1>::difference_type _D1;
14130b57cec5SDimitry Andric    _D1 __l1 = _VSTD::distance(__first1, __last1);
14140b57cec5SDimitry Andric
14150b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator2>::difference_type _D2;
14160b57cec5SDimitry Andric    _D2 __l2 = _VSTD::distance(__first2, __last2);
14170b57cec5SDimitry Andric    if (__l1 != __l2)
14180b57cec5SDimitry Andric        return false;
14190b57cec5SDimitry Andric
14200b57cec5SDimitry Andric    // For each element in [f1, l1) see if there are the same number of
14210b57cec5SDimitry Andric    //    equal elements in [f2, l2)
14220b57cec5SDimitry Andric    for (_ForwardIterator1 __i = __first1; __i != __last1; ++__i)
14230b57cec5SDimitry Andric    {
14240b57cec5SDimitry Andric    //  Have we already counted the number of *__i in [f1, l1)?
14250b57cec5SDimitry Andric        _ForwardIterator1 __match = __first1;
14260b57cec5SDimitry Andric        for (; __match != __i; ++__match)
14270b57cec5SDimitry Andric            if (__pred(*__match, *__i))
14280b57cec5SDimitry Andric                break;
14290b57cec5SDimitry Andric        if (__match == __i) {
14300b57cec5SDimitry Andric            // Count number of *__i in [f2, l2)
14310b57cec5SDimitry Andric            _D1 __c2 = 0;
14320b57cec5SDimitry Andric            for (_ForwardIterator2 __j = __first2; __j != __last2; ++__j)
14330b57cec5SDimitry Andric                if (__pred(*__i, *__j))
14340b57cec5SDimitry Andric                    ++__c2;
14350b57cec5SDimitry Andric            if (__c2 == 0)
14360b57cec5SDimitry Andric                return false;
14370b57cec5SDimitry Andric            // Count number of *__i in [__i, l1) (we can start with 1)
14380b57cec5SDimitry Andric            _D1 __c1 = 1;
14390b57cec5SDimitry Andric            for (_ForwardIterator1 __j = _VSTD::next(__i); __j != __last1; ++__j)
14400b57cec5SDimitry Andric                if (__pred(*__i, *__j))
14410b57cec5SDimitry Andric                    ++__c1;
14420b57cec5SDimitry Andric            if (__c1 != __c2)
14430b57cec5SDimitry Andric                return false;
14440b57cec5SDimitry Andric        }
14450b57cec5SDimitry Andric    }
14460b57cec5SDimitry Andric    return true;
14470b57cec5SDimitry Andric}
14480b57cec5SDimitry Andric
14490b57cec5SDimitry Andrictemplate<class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
14500b57cec5SDimitry Andric_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
14510b57cec5SDimitry Andric__is_permutation(_RandomAccessIterator1 __first1, _RandomAccessIterator2 __last1,
14520b57cec5SDimitry Andric               _RandomAccessIterator1 __first2, _RandomAccessIterator2 __last2,
14530b57cec5SDimitry Andric               _BinaryPredicate __pred,
14540b57cec5SDimitry Andric               random_access_iterator_tag, random_access_iterator_tag )
14550b57cec5SDimitry Andric{
14560b57cec5SDimitry Andric    if ( _VSTD::distance(__first1, __last1) != _VSTD::distance(__first2, __last2))
14570b57cec5SDimitry Andric        return false;
14580b57cec5SDimitry Andric    return _VSTD::is_permutation<_RandomAccessIterator1, _RandomAccessIterator2,
14590b57cec5SDimitry Andric                                 typename add_lvalue_reference<_BinaryPredicate>::type>
14600b57cec5SDimitry Andric                                (__first1, __last1, __first2, __pred );
14610b57cec5SDimitry Andric}
14620b57cec5SDimitry Andric
14630b57cec5SDimitry Andrictemplate<class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
14640b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
14650b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
14660b57cec5SDimitry Andricbool
14670b57cec5SDimitry Andricis_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
14680b57cec5SDimitry Andric               _ForwardIterator2 __first2, _ForwardIterator2 __last2,
14690b57cec5SDimitry Andric               _BinaryPredicate __pred )
14700b57cec5SDimitry Andric{
14710b57cec5SDimitry Andric    return _VSTD::__is_permutation<typename add_lvalue_reference<_BinaryPredicate>::type>
14720b57cec5SDimitry Andric       (__first1, __last1, __first2, __last2, __pred,
14730b57cec5SDimitry Andric        typename iterator_traits<_ForwardIterator1>::iterator_category(),
14740b57cec5SDimitry Andric        typename iterator_traits<_ForwardIterator2>::iterator_category());
14750b57cec5SDimitry Andric}
14760b57cec5SDimitry Andric
14770b57cec5SDimitry Andrictemplate<class _ForwardIterator1, class _ForwardIterator2>
14780b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
14790b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
14800b57cec5SDimitry Andricbool
14810b57cec5SDimitry Andricis_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
14820b57cec5SDimitry Andric               _ForwardIterator2 __first2, _ForwardIterator2 __last2)
14830b57cec5SDimitry Andric{
14840b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
14850b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
14860b57cec5SDimitry Andric    return _VSTD::__is_permutation(__first1, __last1, __first2, __last2,
14870b57cec5SDimitry Andric        __equal_to<__v1, __v2>(),
14880b57cec5SDimitry Andric        typename iterator_traits<_ForwardIterator1>::iterator_category(),
14890b57cec5SDimitry Andric        typename iterator_traits<_ForwardIterator2>::iterator_category());
14900b57cec5SDimitry Andric}
14910b57cec5SDimitry Andric#endif
14920b57cec5SDimitry Andric
14930b57cec5SDimitry Andric// search
14940b57cec5SDimitry Andric// __search is in <functional>
14950b57cec5SDimitry Andric
14960b57cec5SDimitry Andrictemplate <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
14970b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
14980b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
14990b57cec5SDimitry Andric_ForwardIterator1
15000b57cec5SDimitry Andricsearch(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
15010b57cec5SDimitry Andric       _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred)
15020b57cec5SDimitry Andric{
15030b57cec5SDimitry Andric    return _VSTD::__search<typename add_lvalue_reference<_BinaryPredicate>::type>
15040b57cec5SDimitry Andric                         (__first1, __last1, __first2, __last2, __pred,
15050b57cec5SDimitry Andric                          typename iterator_traits<_ForwardIterator1>::iterator_category(),
15060b57cec5SDimitry Andric                          typename iterator_traits<_ForwardIterator2>::iterator_category())
15070b57cec5SDimitry Andric            .first;
15080b57cec5SDimitry Andric}
15090b57cec5SDimitry Andric
15100b57cec5SDimitry Andrictemplate <class _ForwardIterator1, class _ForwardIterator2>
15110b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
15120b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
15130b57cec5SDimitry Andric_ForwardIterator1
15140b57cec5SDimitry Andricsearch(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
15150b57cec5SDimitry Andric       _ForwardIterator2 __first2, _ForwardIterator2 __last2)
15160b57cec5SDimitry Andric{
15170b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
15180b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
15190b57cec5SDimitry Andric    return _VSTD::search(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
15200b57cec5SDimitry Andric}
15210b57cec5SDimitry Andric
15220b57cec5SDimitry Andric
15230b57cec5SDimitry Andric#if _LIBCPP_STD_VER > 14
15240b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Searcher>
15250b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
15260b57cec5SDimitry Andric_ForwardIterator search(_ForwardIterator __f, _ForwardIterator __l, const _Searcher &__s)
15270b57cec5SDimitry Andric{ return __s(__f, __l).first; }
15280b57cec5SDimitry Andric#endif
15290b57cec5SDimitry Andric
15300b57cec5SDimitry Andric// search_n
15310b57cec5SDimitry Andric
15320b57cec5SDimitry Andrictemplate <class _BinaryPredicate, class _ForwardIterator, class _Size, class _Tp>
15330b57cec5SDimitry Andric_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
15340b57cec5SDimitry Andric__search_n(_ForwardIterator __first, _ForwardIterator __last,
15350b57cec5SDimitry Andric           _Size __count, const _Tp& __value_, _BinaryPredicate __pred, forward_iterator_tag)
15360b57cec5SDimitry Andric{
15370b57cec5SDimitry Andric    if (__count <= 0)
15380b57cec5SDimitry Andric        return __first;
15390b57cec5SDimitry Andric    while (true)
15400b57cec5SDimitry Andric    {
15410b57cec5SDimitry Andric        // Find first element in sequence that matchs __value_, with a mininum of loop checks
15420b57cec5SDimitry Andric        while (true)
15430b57cec5SDimitry Andric        {
15440b57cec5SDimitry Andric            if (__first == __last)  // return __last if no element matches __value_
15450b57cec5SDimitry Andric                return __last;
15460b57cec5SDimitry Andric            if (__pred(*__first, __value_))
15470b57cec5SDimitry Andric                break;
15480b57cec5SDimitry Andric            ++__first;
15490b57cec5SDimitry Andric        }
15500b57cec5SDimitry Andric        // *__first matches __value_, now match elements after here
15510b57cec5SDimitry Andric        _ForwardIterator __m = __first;
15520b57cec5SDimitry Andric        _Size __c(0);
15530b57cec5SDimitry Andric        while (true)
15540b57cec5SDimitry Andric        {
15550b57cec5SDimitry Andric            if (++__c == __count)  // If pattern exhausted, __first is the answer (works for 1 element pattern)
15560b57cec5SDimitry Andric                return __first;
15570b57cec5SDimitry Andric            if (++__m == __last)  // Otherwise if source exhaused, pattern not found
15580b57cec5SDimitry Andric                return __last;
15590b57cec5SDimitry Andric            if (!__pred(*__m, __value_))  // if there is a mismatch, restart with a new __first
15600b57cec5SDimitry Andric            {
15610b57cec5SDimitry Andric                __first = __m;
15620b57cec5SDimitry Andric                ++__first;
15630b57cec5SDimitry Andric                break;
15640b57cec5SDimitry Andric            }  // else there is a match, check next elements
15650b57cec5SDimitry Andric        }
15660b57cec5SDimitry Andric    }
15670b57cec5SDimitry Andric}
15680b57cec5SDimitry Andric
15690b57cec5SDimitry Andrictemplate <class _BinaryPredicate, class _RandomAccessIterator, class _Size, class _Tp>
15700b57cec5SDimitry Andric_LIBCPP_CONSTEXPR_AFTER_CXX17 _RandomAccessIterator
15710b57cec5SDimitry Andric__search_n(_RandomAccessIterator __first, _RandomAccessIterator __last,
15720b57cec5SDimitry Andric           _Size __count, const _Tp& __value_, _BinaryPredicate __pred, random_access_iterator_tag)
15730b57cec5SDimitry Andric{
15740b57cec5SDimitry Andric    if (__count <= 0)
15750b57cec5SDimitry Andric        return __first;
15760b57cec5SDimitry Andric    _Size __len = static_cast<_Size>(__last - __first);
15770b57cec5SDimitry Andric    if (__len < __count)
15780b57cec5SDimitry Andric        return __last;
15790b57cec5SDimitry Andric    const _RandomAccessIterator __s = __last - (__count - 1);  // Start of pattern match can't go beyond here
15800b57cec5SDimitry Andric    while (true)
15810b57cec5SDimitry Andric    {
15820b57cec5SDimitry Andric        // Find first element in sequence that matchs __value_, with a mininum of loop checks
15830b57cec5SDimitry Andric        while (true)
15840b57cec5SDimitry Andric        {
15850b57cec5SDimitry Andric            if (__first >= __s)  // return __last if no element matches __value_
15860b57cec5SDimitry Andric                return __last;
15870b57cec5SDimitry Andric            if (__pred(*__first, __value_))
15880b57cec5SDimitry Andric                break;
15890b57cec5SDimitry Andric            ++__first;
15900b57cec5SDimitry Andric        }
15910b57cec5SDimitry Andric        // *__first matches __value_, now match elements after here
15920b57cec5SDimitry Andric        _RandomAccessIterator __m = __first;
15930b57cec5SDimitry Andric        _Size __c(0);
15940b57cec5SDimitry Andric        while (true)
15950b57cec5SDimitry Andric        {
15960b57cec5SDimitry Andric            if (++__c == __count)  // If pattern exhausted, __first is the answer (works for 1 element pattern)
15970b57cec5SDimitry Andric                return __first;
15980b57cec5SDimitry Andric             ++__m;          // no need to check range on __m because __s guarantees we have enough source
15990b57cec5SDimitry Andric            if (!__pred(*__m, __value_))  // if there is a mismatch, restart with a new __first
16000b57cec5SDimitry Andric            {
16010b57cec5SDimitry Andric                __first = __m;
16020b57cec5SDimitry Andric                ++__first;
16030b57cec5SDimitry Andric                break;
16040b57cec5SDimitry Andric            }  // else there is a match, check next elements
16050b57cec5SDimitry Andric        }
16060b57cec5SDimitry Andric    }
16070b57cec5SDimitry Andric}
16080b57cec5SDimitry Andric
16090b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Size, class _Tp, class _BinaryPredicate>
16100b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
16110b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
16120b57cec5SDimitry Andric_ForwardIterator
16130b57cec5SDimitry Andricsearch_n(_ForwardIterator __first, _ForwardIterator __last,
16140b57cec5SDimitry Andric         _Size __count, const _Tp& __value_, _BinaryPredicate __pred)
16150b57cec5SDimitry Andric{
16160b57cec5SDimitry Andric    return _VSTD::__search_n<typename add_lvalue_reference<_BinaryPredicate>::type>
16170b57cec5SDimitry Andric           (__first, __last, __convert_to_integral(__count), __value_, __pred,
16180b57cec5SDimitry Andric           typename iterator_traits<_ForwardIterator>::iterator_category());
16190b57cec5SDimitry Andric}
16200b57cec5SDimitry Andric
16210b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Size, class _Tp>
16220b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
16230b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
16240b57cec5SDimitry Andric_ForwardIterator
16250b57cec5SDimitry Andricsearch_n(_ForwardIterator __first, _ForwardIterator __last, _Size __count, const _Tp& __value_)
16260b57cec5SDimitry Andric{
16270b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator>::value_type __v;
16280b57cec5SDimitry Andric    return _VSTD::search_n(__first, __last, __convert_to_integral(__count),
16290b57cec5SDimitry Andric                           __value_, __equal_to<__v, _Tp>());
16300b57cec5SDimitry Andric}
16310b57cec5SDimitry Andric
16320b57cec5SDimitry Andric// copy
16330b57cec5SDimitry Andrictemplate <class _Iter>
16340b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
16350b57cec5SDimitry Andric_Iter
16360b57cec5SDimitry Andric__unwrap_iter(_Iter __i)
16370b57cec5SDimitry Andric{
16380b57cec5SDimitry Andric    return __i;
16390b57cec5SDimitry Andric}
16400b57cec5SDimitry Andric
16410b57cec5SDimitry Andrictemplate <class _Tp>
16420b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
16430b57cec5SDimitry Andrictypename enable_if
16440b57cec5SDimitry Andric<
16450b57cec5SDimitry Andric    is_trivially_copy_assignable<_Tp>::value,
16460b57cec5SDimitry Andric    _Tp*
16470b57cec5SDimitry Andric>::type
16480b57cec5SDimitry Andric__unwrap_iter(move_iterator<_Tp*> __i)
16490b57cec5SDimitry Andric{
16500b57cec5SDimitry Andric    return __i.base();
16510b57cec5SDimitry Andric}
16520b57cec5SDimitry Andric
16530b57cec5SDimitry Andric#if _LIBCPP_DEBUG_LEVEL < 2
16540b57cec5SDimitry Andric
16550b57cec5SDimitry Andrictemplate <class _Tp>
16560b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_IF_NODEBUG
16570b57cec5SDimitry Andrictypename enable_if
16580b57cec5SDimitry Andric<
16590b57cec5SDimitry Andric    is_trivially_copy_assignable<_Tp>::value,
16600b57cec5SDimitry Andric    _Tp*
16610b57cec5SDimitry Andric>::type
16620b57cec5SDimitry Andric__unwrap_iter(__wrap_iter<_Tp*> __i)
16630b57cec5SDimitry Andric{
16640b57cec5SDimitry Andric    return __i.base();
16650b57cec5SDimitry Andric}
16660b57cec5SDimitry Andric
16670b57cec5SDimitry Andrictemplate <class _Tp>
16680b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_IF_NODEBUG
16690b57cec5SDimitry Andrictypename enable_if
16700b57cec5SDimitry Andric<
16710b57cec5SDimitry Andric    is_trivially_copy_assignable<_Tp>::value,
16720b57cec5SDimitry Andric    const _Tp*
16730b57cec5SDimitry Andric>::type
16740b57cec5SDimitry Andric__unwrap_iter(__wrap_iter<const _Tp*> __i)
16750b57cec5SDimitry Andric{
16760b57cec5SDimitry Andric    return __i.base();
16770b57cec5SDimitry Andric}
16780b57cec5SDimitry Andric
16790b57cec5SDimitry Andric#else
16800b57cec5SDimitry Andric
16810b57cec5SDimitry Andrictemplate <class _Tp>
16820b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_IF_NODEBUG
16830b57cec5SDimitry Andrictypename enable_if
16840b57cec5SDimitry Andric<
16850b57cec5SDimitry Andric    is_trivially_copy_assignable<_Tp>::value,
16860b57cec5SDimitry Andric    __wrap_iter<_Tp*>
16870b57cec5SDimitry Andric>::type
16880b57cec5SDimitry Andric__unwrap_iter(__wrap_iter<_Tp*> __i)
16890b57cec5SDimitry Andric{
16900b57cec5SDimitry Andric    return __i;
16910b57cec5SDimitry Andric}
16920b57cec5SDimitry Andric
16930b57cec5SDimitry Andric#endif  // _LIBCPP_DEBUG_LEVEL < 2
16940b57cec5SDimitry Andric
16950b57cec5SDimitry Andrictemplate <class _InputIterator, class _OutputIterator>
16960b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
16970b57cec5SDimitry Andric_OutputIterator
16980b57cec5SDimitry Andric__copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
16990b57cec5SDimitry Andric{
17000b57cec5SDimitry Andric    for (; __first != __last; ++__first, (void) ++__result)
17010b57cec5SDimitry Andric        *__result = *__first;
17020b57cec5SDimitry Andric    return __result;
17030b57cec5SDimitry Andric}
17040b57cec5SDimitry Andric
17050b57cec5SDimitry Andrictemplate <class _Tp, class _Up>
17060b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
17070b57cec5SDimitry Andrictypename enable_if
17080b57cec5SDimitry Andric<
17090b57cec5SDimitry Andric    is_same<typename remove_const<_Tp>::type, _Up>::value &&
17100b57cec5SDimitry Andric    is_trivially_copy_assignable<_Up>::value,
17110b57cec5SDimitry Andric    _Up*
17120b57cec5SDimitry Andric>::type
17130b57cec5SDimitry Andric__copy(_Tp* __first, _Tp* __last, _Up* __result)
17140b57cec5SDimitry Andric{
17150b57cec5SDimitry Andric    const size_t __n = static_cast<size_t>(__last - __first);
17160b57cec5SDimitry Andric    if (__n > 0)
17170b57cec5SDimitry Andric        _VSTD::memmove(__result, __first, __n * sizeof(_Up));
17180b57cec5SDimitry Andric    return __result + __n;
17190b57cec5SDimitry Andric}
17200b57cec5SDimitry Andric
17210b57cec5SDimitry Andrictemplate <class _InputIterator, class _OutputIterator>
17220b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
17230b57cec5SDimitry Andric_OutputIterator
17240b57cec5SDimitry Andriccopy(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
17250b57cec5SDimitry Andric{
17260b57cec5SDimitry Andric    return _VSTD::__copy(__unwrap_iter(__first), __unwrap_iter(__last), __unwrap_iter(__result));
17270b57cec5SDimitry Andric}
17280b57cec5SDimitry Andric
17290b57cec5SDimitry Andric// copy_backward
17300b57cec5SDimitry Andric
17310b57cec5SDimitry Andrictemplate <class _BidirectionalIterator, class _OutputIterator>
17320b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
17330b57cec5SDimitry Andric_OutputIterator
17340b57cec5SDimitry Andric__copy_backward(_BidirectionalIterator __first, _BidirectionalIterator __last, _OutputIterator __result)
17350b57cec5SDimitry Andric{
17360b57cec5SDimitry Andric    while (__first != __last)
17370b57cec5SDimitry Andric        *--__result = *--__last;
17380b57cec5SDimitry Andric    return __result;
17390b57cec5SDimitry Andric}
17400b57cec5SDimitry Andric
17410b57cec5SDimitry Andrictemplate <class _Tp, class _Up>
17420b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
17430b57cec5SDimitry Andrictypename enable_if
17440b57cec5SDimitry Andric<
17450b57cec5SDimitry Andric    is_same<typename remove_const<_Tp>::type, _Up>::value &&
17460b57cec5SDimitry Andric    is_trivially_copy_assignable<_Up>::value,
17470b57cec5SDimitry Andric    _Up*
17480b57cec5SDimitry Andric>::type
17490b57cec5SDimitry Andric__copy_backward(_Tp* __first, _Tp* __last, _Up* __result)
17500b57cec5SDimitry Andric{
17510b57cec5SDimitry Andric    const size_t __n = static_cast<size_t>(__last - __first);
17520b57cec5SDimitry Andric    if (__n > 0)
17530b57cec5SDimitry Andric    {
17540b57cec5SDimitry Andric        __result -= __n;
17550b57cec5SDimitry Andric        _VSTD::memmove(__result, __first, __n * sizeof(_Up));
17560b57cec5SDimitry Andric    }
17570b57cec5SDimitry Andric    return __result;
17580b57cec5SDimitry Andric}
17590b57cec5SDimitry Andric
17600b57cec5SDimitry Andrictemplate <class _BidirectionalIterator1, class _BidirectionalIterator2>
17610b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
17620b57cec5SDimitry Andric_BidirectionalIterator2
17630b57cec5SDimitry Andriccopy_backward(_BidirectionalIterator1 __first, _BidirectionalIterator1 __last,
17640b57cec5SDimitry Andric              _BidirectionalIterator2 __result)
17650b57cec5SDimitry Andric{
17660b57cec5SDimitry Andric    return _VSTD::__copy_backward(__unwrap_iter(__first),
17670b57cec5SDimitry Andric                                  __unwrap_iter(__last),
17680b57cec5SDimitry Andric                                  __unwrap_iter(__result));
17690b57cec5SDimitry Andric}
17700b57cec5SDimitry Andric
17710b57cec5SDimitry Andric// copy_if
17720b57cec5SDimitry Andric
17730b57cec5SDimitry Andrictemplate<class _InputIterator, class _OutputIterator, class _Predicate>
17740b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
17750b57cec5SDimitry Andric_OutputIterator
17760b57cec5SDimitry Andriccopy_if(_InputIterator __first, _InputIterator __last,
17770b57cec5SDimitry Andric        _OutputIterator __result, _Predicate __pred)
17780b57cec5SDimitry Andric{
17790b57cec5SDimitry Andric    for (; __first != __last; ++__first)
17800b57cec5SDimitry Andric    {
17810b57cec5SDimitry Andric        if (__pred(*__first))
17820b57cec5SDimitry Andric        {
17830b57cec5SDimitry Andric            *__result = *__first;
17840b57cec5SDimitry Andric            ++__result;
17850b57cec5SDimitry Andric        }
17860b57cec5SDimitry Andric    }
17870b57cec5SDimitry Andric    return __result;
17880b57cec5SDimitry Andric}
17890b57cec5SDimitry Andric
17900b57cec5SDimitry Andric// copy_n
17910b57cec5SDimitry Andric
17920b57cec5SDimitry Andrictemplate<class _InputIterator, class _Size, class _OutputIterator>
17930b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
17940b57cec5SDimitry Andrictypename enable_if
17950b57cec5SDimitry Andric<
17960b57cec5SDimitry Andric    __is_input_iterator<_InputIterator>::value &&
17970b57cec5SDimitry Andric   !__is_random_access_iterator<_InputIterator>::value,
17980b57cec5SDimitry Andric    _OutputIterator
17990b57cec5SDimitry Andric>::type
18000b57cec5SDimitry Andriccopy_n(_InputIterator __first, _Size __orig_n, _OutputIterator __result)
18010b57cec5SDimitry Andric{
18020b57cec5SDimitry Andric    typedef decltype(__convert_to_integral(__orig_n)) _IntegralSize;
18030b57cec5SDimitry Andric    _IntegralSize __n = __orig_n;
18040b57cec5SDimitry Andric    if (__n > 0)
18050b57cec5SDimitry Andric    {
18060b57cec5SDimitry Andric        *__result = *__first;
18070b57cec5SDimitry Andric        ++__result;
18080b57cec5SDimitry Andric        for (--__n; __n > 0; --__n)
18090b57cec5SDimitry Andric        {
18100b57cec5SDimitry Andric            ++__first;
18110b57cec5SDimitry Andric            *__result = *__first;
18120b57cec5SDimitry Andric            ++__result;
18130b57cec5SDimitry Andric        }
18140b57cec5SDimitry Andric    }
18150b57cec5SDimitry Andric    return __result;
18160b57cec5SDimitry Andric}
18170b57cec5SDimitry Andric
18180b57cec5SDimitry Andrictemplate<class _InputIterator, class _Size, class _OutputIterator>
18190b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
18200b57cec5SDimitry Andrictypename enable_if
18210b57cec5SDimitry Andric<
18220b57cec5SDimitry Andric    __is_random_access_iterator<_InputIterator>::value,
18230b57cec5SDimitry Andric    _OutputIterator
18240b57cec5SDimitry Andric>::type
18250b57cec5SDimitry Andriccopy_n(_InputIterator __first, _Size __orig_n, _OutputIterator __result)
18260b57cec5SDimitry Andric{
18270b57cec5SDimitry Andric    typedef decltype(__convert_to_integral(__orig_n)) _IntegralSize;
18280b57cec5SDimitry Andric    _IntegralSize __n = __orig_n;
18290b57cec5SDimitry Andric    return _VSTD::copy(__first, __first + __n, __result);
18300b57cec5SDimitry Andric}
18310b57cec5SDimitry Andric
18320b57cec5SDimitry Andric// move
18330b57cec5SDimitry Andric
18340b57cec5SDimitry Andrictemplate <class _InputIterator, class _OutputIterator>
18350b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
18360b57cec5SDimitry Andric_OutputIterator
18370b57cec5SDimitry Andric__move(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
18380b57cec5SDimitry Andric{
18390b57cec5SDimitry Andric    for (; __first != __last; ++__first, (void) ++__result)
18400b57cec5SDimitry Andric        *__result = _VSTD::move(*__first);
18410b57cec5SDimitry Andric    return __result;
18420b57cec5SDimitry Andric}
18430b57cec5SDimitry Andric
18440b57cec5SDimitry Andrictemplate <class _Tp, class _Up>
18450b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
18460b57cec5SDimitry Andrictypename enable_if
18470b57cec5SDimitry Andric<
18480b57cec5SDimitry Andric    is_same<typename remove_const<_Tp>::type, _Up>::value &&
18490b57cec5SDimitry Andric    is_trivially_copy_assignable<_Up>::value,
18500b57cec5SDimitry Andric    _Up*
18510b57cec5SDimitry Andric>::type
18520b57cec5SDimitry Andric__move(_Tp* __first, _Tp* __last, _Up* __result)
18530b57cec5SDimitry Andric{
18540b57cec5SDimitry Andric    const size_t __n = static_cast<size_t>(__last - __first);
18550b57cec5SDimitry Andric    if (__n > 0)
18560b57cec5SDimitry Andric        _VSTD::memmove(__result, __first, __n * sizeof(_Up));
18570b57cec5SDimitry Andric    return __result + __n;
18580b57cec5SDimitry Andric}
18590b57cec5SDimitry Andric
18600b57cec5SDimitry Andrictemplate <class _InputIterator, class _OutputIterator>
18610b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
18620b57cec5SDimitry Andric_OutputIterator
18630b57cec5SDimitry Andricmove(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
18640b57cec5SDimitry Andric{
18650b57cec5SDimitry Andric    return _VSTD::__move(__unwrap_iter(__first), __unwrap_iter(__last), __unwrap_iter(__result));
18660b57cec5SDimitry Andric}
18670b57cec5SDimitry Andric
18680b57cec5SDimitry Andric// move_backward
18690b57cec5SDimitry Andric
18700b57cec5SDimitry Andrictemplate <class _InputIterator, class _OutputIterator>
18710b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
18720b57cec5SDimitry Andric_OutputIterator
18730b57cec5SDimitry Andric__move_backward(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
18740b57cec5SDimitry Andric{
18750b57cec5SDimitry Andric    while (__first != __last)
18760b57cec5SDimitry Andric        *--__result = _VSTD::move(*--__last);
18770b57cec5SDimitry Andric    return __result;
18780b57cec5SDimitry Andric}
18790b57cec5SDimitry Andric
18800b57cec5SDimitry Andrictemplate <class _Tp, class _Up>
18810b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
18820b57cec5SDimitry Andrictypename enable_if
18830b57cec5SDimitry Andric<
18840b57cec5SDimitry Andric    is_same<typename remove_const<_Tp>::type, _Up>::value &&
18850b57cec5SDimitry Andric    is_trivially_copy_assignable<_Up>::value,
18860b57cec5SDimitry Andric    _Up*
18870b57cec5SDimitry Andric>::type
18880b57cec5SDimitry Andric__move_backward(_Tp* __first, _Tp* __last, _Up* __result)
18890b57cec5SDimitry Andric{
18900b57cec5SDimitry Andric    const size_t __n = static_cast<size_t>(__last - __first);
18910b57cec5SDimitry Andric    if (__n > 0)
18920b57cec5SDimitry Andric    {
18930b57cec5SDimitry Andric        __result -= __n;
18940b57cec5SDimitry Andric        _VSTD::memmove(__result, __first, __n * sizeof(_Up));
18950b57cec5SDimitry Andric    }
18960b57cec5SDimitry Andric    return __result;
18970b57cec5SDimitry Andric}
18980b57cec5SDimitry Andric
18990b57cec5SDimitry Andrictemplate <class _BidirectionalIterator1, class _BidirectionalIterator2>
19000b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
19010b57cec5SDimitry Andric_BidirectionalIterator2
19020b57cec5SDimitry Andricmove_backward(_BidirectionalIterator1 __first, _BidirectionalIterator1 __last,
19030b57cec5SDimitry Andric              _BidirectionalIterator2 __result)
19040b57cec5SDimitry Andric{
19050b57cec5SDimitry Andric    return _VSTD::__move_backward(__unwrap_iter(__first), __unwrap_iter(__last), __unwrap_iter(__result));
19060b57cec5SDimitry Andric}
19070b57cec5SDimitry Andric
19080b57cec5SDimitry Andric// iter_swap
19090b57cec5SDimitry Andric
19100b57cec5SDimitry Andric// moved to <type_traits> for better swap / noexcept support
19110b57cec5SDimitry Andric
19120b57cec5SDimitry Andric// transform
19130b57cec5SDimitry Andric
19140b57cec5SDimitry Andrictemplate <class _InputIterator, class _OutputIterator, class _UnaryOperation>
19150b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
19160b57cec5SDimitry Andric_OutputIterator
19170b57cec5SDimitry Andrictransform(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _UnaryOperation __op)
19180b57cec5SDimitry Andric{
19190b57cec5SDimitry Andric    for (; __first != __last; ++__first, (void) ++__result)
19200b57cec5SDimitry Andric        *__result = __op(*__first);
19210b57cec5SDimitry Andric    return __result;
19220b57cec5SDimitry Andric}
19230b57cec5SDimitry Andric
19240b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _BinaryOperation>
19250b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
19260b57cec5SDimitry Andric_OutputIterator
19270b57cec5SDimitry Andrictransform(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2,
19280b57cec5SDimitry Andric          _OutputIterator __result, _BinaryOperation __binary_op)
19290b57cec5SDimitry Andric{
19300b57cec5SDimitry Andric    for (; __first1 != __last1; ++__first1, (void) ++__first2, ++__result)
19310b57cec5SDimitry Andric        *__result = __binary_op(*__first1, *__first2);
19320b57cec5SDimitry Andric    return __result;
19330b57cec5SDimitry Andric}
19340b57cec5SDimitry Andric
19350b57cec5SDimitry Andric// replace
19360b57cec5SDimitry Andric
19370b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Tp>
19380b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
19390b57cec5SDimitry Andricvoid
19400b57cec5SDimitry Andricreplace(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __old_value, const _Tp& __new_value)
19410b57cec5SDimitry Andric{
19420b57cec5SDimitry Andric    for (; __first != __last; ++__first)
19430b57cec5SDimitry Andric        if (*__first == __old_value)
19440b57cec5SDimitry Andric            *__first = __new_value;
19450b57cec5SDimitry Andric}
19460b57cec5SDimitry Andric
19470b57cec5SDimitry Andric// replace_if
19480b57cec5SDimitry Andric
19490b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Predicate, class _Tp>
19500b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
19510b57cec5SDimitry Andricvoid
19520b57cec5SDimitry Andricreplace_if(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred, const _Tp& __new_value)
19530b57cec5SDimitry Andric{
19540b57cec5SDimitry Andric    for (; __first != __last; ++__first)
19550b57cec5SDimitry Andric        if (__pred(*__first))
19560b57cec5SDimitry Andric            *__first = __new_value;
19570b57cec5SDimitry Andric}
19580b57cec5SDimitry Andric
19590b57cec5SDimitry Andric// replace_copy
19600b57cec5SDimitry Andric
19610b57cec5SDimitry Andrictemplate <class _InputIterator, class _OutputIterator, class _Tp>
19620b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
19630b57cec5SDimitry Andric_OutputIterator
19640b57cec5SDimitry Andricreplace_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result,
19650b57cec5SDimitry Andric             const _Tp& __old_value, const _Tp& __new_value)
19660b57cec5SDimitry Andric{
19670b57cec5SDimitry Andric    for (; __first != __last; ++__first, (void) ++__result)
19680b57cec5SDimitry Andric        if (*__first == __old_value)
19690b57cec5SDimitry Andric            *__result = __new_value;
19700b57cec5SDimitry Andric        else
19710b57cec5SDimitry Andric            *__result = *__first;
19720b57cec5SDimitry Andric    return __result;
19730b57cec5SDimitry Andric}
19740b57cec5SDimitry Andric
19750b57cec5SDimitry Andric// replace_copy_if
19760b57cec5SDimitry Andric
19770b57cec5SDimitry Andrictemplate <class _InputIterator, class _OutputIterator, class _Predicate, class _Tp>
19780b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
19790b57cec5SDimitry Andric_OutputIterator
19800b57cec5SDimitry Andricreplace_copy_if(_InputIterator __first, _InputIterator __last, _OutputIterator __result,
19810b57cec5SDimitry Andric                _Predicate __pred, const _Tp& __new_value)
19820b57cec5SDimitry Andric{
19830b57cec5SDimitry Andric    for (; __first != __last; ++__first, (void) ++__result)
19840b57cec5SDimitry Andric        if (__pred(*__first))
19850b57cec5SDimitry Andric            *__result = __new_value;
19860b57cec5SDimitry Andric        else
19870b57cec5SDimitry Andric            *__result = *__first;
19880b57cec5SDimitry Andric    return __result;
19890b57cec5SDimitry Andric}
19900b57cec5SDimitry Andric
19910b57cec5SDimitry Andric// fill_n
19920b57cec5SDimitry Andric
19930b57cec5SDimitry Andrictemplate <class _OutputIterator, class _Size, class _Tp>
19940b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
19950b57cec5SDimitry Andric_OutputIterator
19960b57cec5SDimitry Andric__fill_n(_OutputIterator __first, _Size __n, const _Tp& __value_)
19970b57cec5SDimitry Andric{
19980b57cec5SDimitry Andric    for (; __n > 0; ++__first, (void) --__n)
19990b57cec5SDimitry Andric        *__first = __value_;
20000b57cec5SDimitry Andric    return __first;
20010b57cec5SDimitry Andric}
20020b57cec5SDimitry Andric
20030b57cec5SDimitry Andrictemplate <class _OutputIterator, class _Size, class _Tp>
20040b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
20050b57cec5SDimitry Andric_OutputIterator
20060b57cec5SDimitry Andricfill_n(_OutputIterator __first, _Size __n, const _Tp& __value_)
20070b57cec5SDimitry Andric{
20080b57cec5SDimitry Andric   return _VSTD::__fill_n(__first, __convert_to_integral(__n), __value_);
20090b57cec5SDimitry Andric}
20100b57cec5SDimitry Andric
20110b57cec5SDimitry Andric// fill
20120b57cec5SDimitry Andric
20130b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Tp>
20140b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
20150b57cec5SDimitry Andricvoid
20160b57cec5SDimitry Andric__fill(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, forward_iterator_tag)
20170b57cec5SDimitry Andric{
20180b57cec5SDimitry Andric    for (; __first != __last; ++__first)
20190b57cec5SDimitry Andric        *__first = __value_;
20200b57cec5SDimitry Andric}
20210b57cec5SDimitry Andric
20220b57cec5SDimitry Andrictemplate <class _RandomAccessIterator, class _Tp>
20230b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
20240b57cec5SDimitry Andricvoid
20250b57cec5SDimitry Andric__fill(_RandomAccessIterator __first, _RandomAccessIterator __last, const _Tp& __value_, random_access_iterator_tag)
20260b57cec5SDimitry Andric{
20270b57cec5SDimitry Andric    _VSTD::fill_n(__first, __last - __first, __value_);
20280b57cec5SDimitry Andric}
20290b57cec5SDimitry Andric
20300b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Tp>
20310b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
20320b57cec5SDimitry Andricvoid
20330b57cec5SDimitry Andricfill(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
20340b57cec5SDimitry Andric{
20350b57cec5SDimitry Andric    _VSTD::__fill(__first, __last, __value_, typename iterator_traits<_ForwardIterator>::iterator_category());
20360b57cec5SDimitry Andric}
20370b57cec5SDimitry Andric
20380b57cec5SDimitry Andric// generate
20390b57cec5SDimitry Andric
20400b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Generator>
20410b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
20420b57cec5SDimitry Andricvoid
20430b57cec5SDimitry Andricgenerate(_ForwardIterator __first, _ForwardIterator __last, _Generator __gen)
20440b57cec5SDimitry Andric{
20450b57cec5SDimitry Andric    for (; __first != __last; ++__first)
20460b57cec5SDimitry Andric        *__first = __gen();
20470b57cec5SDimitry Andric}
20480b57cec5SDimitry Andric
20490b57cec5SDimitry Andric// generate_n
20500b57cec5SDimitry Andric
20510b57cec5SDimitry Andrictemplate <class _OutputIterator, class _Size, class _Generator>
20520b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
20530b57cec5SDimitry Andric_OutputIterator
20540b57cec5SDimitry Andricgenerate_n(_OutputIterator __first, _Size __orig_n, _Generator __gen)
20550b57cec5SDimitry Andric{
20560b57cec5SDimitry Andric    typedef decltype(__convert_to_integral(__orig_n)) _IntegralSize;
20570b57cec5SDimitry Andric    _IntegralSize __n = __orig_n;
20580b57cec5SDimitry Andric    for (; __n > 0; ++__first, (void) --__n)
20590b57cec5SDimitry Andric        *__first = __gen();
20600b57cec5SDimitry Andric    return __first;
20610b57cec5SDimitry Andric}
20620b57cec5SDimitry Andric
20630b57cec5SDimitry Andric// remove
20640b57cec5SDimitry Andric
20650b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Tp>
20660b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
20670b57cec5SDimitry Andricremove(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
20680b57cec5SDimitry Andric{
20690b57cec5SDimitry Andric    __first = _VSTD::find(__first, __last, __value_);
20700b57cec5SDimitry Andric    if (__first != __last)
20710b57cec5SDimitry Andric    {
20720b57cec5SDimitry Andric        _ForwardIterator __i = __first;
20730b57cec5SDimitry Andric        while (++__i != __last)
20740b57cec5SDimitry Andric        {
20750b57cec5SDimitry Andric            if (!(*__i == __value_))
20760b57cec5SDimitry Andric            {
20770b57cec5SDimitry Andric                *__first = _VSTD::move(*__i);
20780b57cec5SDimitry Andric                ++__first;
20790b57cec5SDimitry Andric            }
20800b57cec5SDimitry Andric        }
20810b57cec5SDimitry Andric    }
20820b57cec5SDimitry Andric    return __first;
20830b57cec5SDimitry Andric}
20840b57cec5SDimitry Andric
20850b57cec5SDimitry Andric// remove_if
20860b57cec5SDimitry Andric
20870b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Predicate>
20880b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
20890b57cec5SDimitry Andricremove_if(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred)
20900b57cec5SDimitry Andric{
20910b57cec5SDimitry Andric    __first = _VSTD::find_if<_ForwardIterator, typename add_lvalue_reference<_Predicate>::type>
20920b57cec5SDimitry Andric                           (__first, __last, __pred);
20930b57cec5SDimitry Andric    if (__first != __last)
20940b57cec5SDimitry Andric    {
20950b57cec5SDimitry Andric        _ForwardIterator __i = __first;
20960b57cec5SDimitry Andric        while (++__i != __last)
20970b57cec5SDimitry Andric        {
20980b57cec5SDimitry Andric            if (!__pred(*__i))
20990b57cec5SDimitry Andric            {
21000b57cec5SDimitry Andric                *__first = _VSTD::move(*__i);
21010b57cec5SDimitry Andric                ++__first;
21020b57cec5SDimitry Andric            }
21030b57cec5SDimitry Andric        }
21040b57cec5SDimitry Andric    }
21050b57cec5SDimitry Andric    return __first;
21060b57cec5SDimitry Andric}
21070b57cec5SDimitry Andric
21080b57cec5SDimitry Andric// remove_copy
21090b57cec5SDimitry Andric
21100b57cec5SDimitry Andrictemplate <class _InputIterator, class _OutputIterator, class _Tp>
21110b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
21120b57cec5SDimitry Andric_OutputIterator
21130b57cec5SDimitry Andricremove_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result, const _Tp& __value_)
21140b57cec5SDimitry Andric{
21150b57cec5SDimitry Andric    for (; __first != __last; ++__first)
21160b57cec5SDimitry Andric    {
21170b57cec5SDimitry Andric        if (!(*__first == __value_))
21180b57cec5SDimitry Andric        {
21190b57cec5SDimitry Andric            *__result = *__first;
21200b57cec5SDimitry Andric            ++__result;
21210b57cec5SDimitry Andric        }
21220b57cec5SDimitry Andric    }
21230b57cec5SDimitry Andric    return __result;
21240b57cec5SDimitry Andric}
21250b57cec5SDimitry Andric
21260b57cec5SDimitry Andric// remove_copy_if
21270b57cec5SDimitry Andric
21280b57cec5SDimitry Andrictemplate <class _InputIterator, class _OutputIterator, class _Predicate>
21290b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
21300b57cec5SDimitry Andric_OutputIterator
21310b57cec5SDimitry Andricremove_copy_if(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _Predicate __pred)
21320b57cec5SDimitry Andric{
21330b57cec5SDimitry Andric    for (; __first != __last; ++__first)
21340b57cec5SDimitry Andric    {
21350b57cec5SDimitry Andric        if (!__pred(*__first))
21360b57cec5SDimitry Andric        {
21370b57cec5SDimitry Andric            *__result = *__first;
21380b57cec5SDimitry Andric            ++__result;
21390b57cec5SDimitry Andric        }
21400b57cec5SDimitry Andric    }
21410b57cec5SDimitry Andric    return __result;
21420b57cec5SDimitry Andric}
21430b57cec5SDimitry Andric
21440b57cec5SDimitry Andric// unique
21450b57cec5SDimitry Andric
21460b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _BinaryPredicate>
21470b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
21480b57cec5SDimitry Andricunique(_ForwardIterator __first, _ForwardIterator __last, _BinaryPredicate __pred)
21490b57cec5SDimitry Andric{
21500b57cec5SDimitry Andric    __first = _VSTD::adjacent_find<_ForwardIterator, typename add_lvalue_reference<_BinaryPredicate>::type>
21510b57cec5SDimitry Andric                                 (__first, __last, __pred);
21520b57cec5SDimitry Andric    if (__first != __last)
21530b57cec5SDimitry Andric    {
21540b57cec5SDimitry Andric        // ...  a  a  ?  ...
21550b57cec5SDimitry Andric        //      f     i
21560b57cec5SDimitry Andric        _ForwardIterator __i = __first;
21570b57cec5SDimitry Andric        for (++__i; ++__i != __last;)
21580b57cec5SDimitry Andric            if (!__pred(*__first, *__i))
21590b57cec5SDimitry Andric                *++__first = _VSTD::move(*__i);
21600b57cec5SDimitry Andric        ++__first;
21610b57cec5SDimitry Andric    }
21620b57cec5SDimitry Andric    return __first;
21630b57cec5SDimitry Andric}
21640b57cec5SDimitry Andric
21650b57cec5SDimitry Andrictemplate <class _ForwardIterator>
21660b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
21670b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
21680b57cec5SDimitry Andric_ForwardIterator
21690b57cec5SDimitry Andricunique(_ForwardIterator __first, _ForwardIterator __last)
21700b57cec5SDimitry Andric{
21710b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator>::value_type __v;
21720b57cec5SDimitry Andric    return _VSTD::unique(__first, __last, __equal_to<__v>());
21730b57cec5SDimitry Andric}
21740b57cec5SDimitry Andric
21750b57cec5SDimitry Andric// unique_copy
21760b57cec5SDimitry Andric
21770b57cec5SDimitry Andrictemplate <class _BinaryPredicate, class _InputIterator, class _OutputIterator>
21780b57cec5SDimitry Andric_LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
21790b57cec5SDimitry Andric__unique_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _BinaryPredicate __pred,
21800b57cec5SDimitry Andric              input_iterator_tag, output_iterator_tag)
21810b57cec5SDimitry Andric{
21820b57cec5SDimitry Andric    if (__first != __last)
21830b57cec5SDimitry Andric    {
21840b57cec5SDimitry Andric        typename iterator_traits<_InputIterator>::value_type __t(*__first);
21850b57cec5SDimitry Andric        *__result = __t;
21860b57cec5SDimitry Andric        ++__result;
21870b57cec5SDimitry Andric        while (++__first != __last)
21880b57cec5SDimitry Andric        {
21890b57cec5SDimitry Andric            if (!__pred(__t, *__first))
21900b57cec5SDimitry Andric            {
21910b57cec5SDimitry Andric                __t = *__first;
21920b57cec5SDimitry Andric                *__result = __t;
21930b57cec5SDimitry Andric                ++__result;
21940b57cec5SDimitry Andric            }
21950b57cec5SDimitry Andric        }
21960b57cec5SDimitry Andric    }
21970b57cec5SDimitry Andric    return __result;
21980b57cec5SDimitry Andric}
21990b57cec5SDimitry Andric
22000b57cec5SDimitry Andrictemplate <class _BinaryPredicate, class _ForwardIterator, class _OutputIterator>
22010b57cec5SDimitry Andric_LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
22020b57cec5SDimitry Andric__unique_copy(_ForwardIterator __first, _ForwardIterator __last, _OutputIterator __result, _BinaryPredicate __pred,
22030b57cec5SDimitry Andric              forward_iterator_tag, output_iterator_tag)
22040b57cec5SDimitry Andric{
22050b57cec5SDimitry Andric    if (__first != __last)
22060b57cec5SDimitry Andric    {
22070b57cec5SDimitry Andric        _ForwardIterator __i = __first;
22080b57cec5SDimitry Andric        *__result = *__i;
22090b57cec5SDimitry Andric        ++__result;
22100b57cec5SDimitry Andric        while (++__first != __last)
22110b57cec5SDimitry Andric        {
22120b57cec5SDimitry Andric            if (!__pred(*__i, *__first))
22130b57cec5SDimitry Andric            {
22140b57cec5SDimitry Andric                *__result = *__first;
22150b57cec5SDimitry Andric                ++__result;
22160b57cec5SDimitry Andric                __i = __first;
22170b57cec5SDimitry Andric            }
22180b57cec5SDimitry Andric        }
22190b57cec5SDimitry Andric    }
22200b57cec5SDimitry Andric    return __result;
22210b57cec5SDimitry Andric}
22220b57cec5SDimitry Andric
22230b57cec5SDimitry Andrictemplate <class _BinaryPredicate, class _InputIterator, class _ForwardIterator>
22240b57cec5SDimitry Andric_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
22250b57cec5SDimitry Andric__unique_copy(_InputIterator __first, _InputIterator __last, _ForwardIterator __result, _BinaryPredicate __pred,
22260b57cec5SDimitry Andric              input_iterator_tag, forward_iterator_tag)
22270b57cec5SDimitry Andric{
22280b57cec5SDimitry Andric    if (__first != __last)
22290b57cec5SDimitry Andric    {
22300b57cec5SDimitry Andric        *__result = *__first;
22310b57cec5SDimitry Andric        while (++__first != __last)
22320b57cec5SDimitry Andric            if (!__pred(*__result, *__first))
22330b57cec5SDimitry Andric                *++__result = *__first;
22340b57cec5SDimitry Andric        ++__result;
22350b57cec5SDimitry Andric    }
22360b57cec5SDimitry Andric    return __result;
22370b57cec5SDimitry Andric}
22380b57cec5SDimitry Andric
22390b57cec5SDimitry Andrictemplate <class _InputIterator, class _OutputIterator, class _BinaryPredicate>
22400b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
22410b57cec5SDimitry Andric_OutputIterator
22420b57cec5SDimitry Andricunique_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _BinaryPredicate __pred)
22430b57cec5SDimitry Andric{
22440b57cec5SDimitry Andric    return _VSTD::__unique_copy<typename add_lvalue_reference<_BinaryPredicate>::type>
22450b57cec5SDimitry Andric                              (__first, __last, __result, __pred,
22460b57cec5SDimitry Andric                               typename iterator_traits<_InputIterator>::iterator_category(),
22470b57cec5SDimitry Andric                               typename iterator_traits<_OutputIterator>::iterator_category());
22480b57cec5SDimitry Andric}
22490b57cec5SDimitry Andric
22500b57cec5SDimitry Andrictemplate <class _InputIterator, class _OutputIterator>
22510b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
22520b57cec5SDimitry Andric_OutputIterator
22530b57cec5SDimitry Andricunique_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
22540b57cec5SDimitry Andric{
22550b57cec5SDimitry Andric    typedef typename iterator_traits<_InputIterator>::value_type __v;
22560b57cec5SDimitry Andric    return _VSTD::unique_copy(__first, __last, __result, __equal_to<__v>());
22570b57cec5SDimitry Andric}
22580b57cec5SDimitry Andric
22590b57cec5SDimitry Andric// reverse
22600b57cec5SDimitry Andric
22610b57cec5SDimitry Andrictemplate <class _BidirectionalIterator>
22620b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
22630b57cec5SDimitry Andricvoid
22640b57cec5SDimitry Andric__reverse(_BidirectionalIterator __first, _BidirectionalIterator __last, bidirectional_iterator_tag)
22650b57cec5SDimitry Andric{
22660b57cec5SDimitry Andric    while (__first != __last)
22670b57cec5SDimitry Andric    {
22680b57cec5SDimitry Andric        if (__first == --__last)
22690b57cec5SDimitry Andric            break;
22700b57cec5SDimitry Andric        _VSTD::iter_swap(__first, __last);
22710b57cec5SDimitry Andric        ++__first;
22720b57cec5SDimitry Andric    }
22730b57cec5SDimitry Andric}
22740b57cec5SDimitry Andric
22750b57cec5SDimitry Andrictemplate <class _RandomAccessIterator>
22760b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
22770b57cec5SDimitry Andricvoid
22780b57cec5SDimitry Andric__reverse(_RandomAccessIterator __first, _RandomAccessIterator __last, random_access_iterator_tag)
22790b57cec5SDimitry Andric{
22800b57cec5SDimitry Andric    if (__first != __last)
22810b57cec5SDimitry Andric        for (; __first < --__last; ++__first)
22820b57cec5SDimitry Andric            _VSTD::iter_swap(__first, __last);
22830b57cec5SDimitry Andric}
22840b57cec5SDimitry Andric
22850b57cec5SDimitry Andrictemplate <class _BidirectionalIterator>
22860b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
22870b57cec5SDimitry Andricvoid
22880b57cec5SDimitry Andricreverse(_BidirectionalIterator __first, _BidirectionalIterator __last)
22890b57cec5SDimitry Andric{
22900b57cec5SDimitry Andric    _VSTD::__reverse(__first, __last, typename iterator_traits<_BidirectionalIterator>::iterator_category());
22910b57cec5SDimitry Andric}
22920b57cec5SDimitry Andric
22930b57cec5SDimitry Andric// reverse_copy
22940b57cec5SDimitry Andric
22950b57cec5SDimitry Andrictemplate <class _BidirectionalIterator, class _OutputIterator>
22960b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
22970b57cec5SDimitry Andric_OutputIterator
22980b57cec5SDimitry Andricreverse_copy(_BidirectionalIterator __first, _BidirectionalIterator __last, _OutputIterator __result)
22990b57cec5SDimitry Andric{
23000b57cec5SDimitry Andric    for (; __first != __last; ++__result)
23010b57cec5SDimitry Andric        *__result = *--__last;
23020b57cec5SDimitry Andric    return __result;
23030b57cec5SDimitry Andric}
23040b57cec5SDimitry Andric
23050b57cec5SDimitry Andric// rotate
23060b57cec5SDimitry Andric
23070b57cec5SDimitry Andrictemplate <class _ForwardIterator>
23080b57cec5SDimitry Andric_ForwardIterator
23090b57cec5SDimitry Andric__rotate_left(_ForwardIterator __first, _ForwardIterator __last)
23100b57cec5SDimitry Andric{
23110b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
23120b57cec5SDimitry Andric    value_type __tmp = _VSTD::move(*__first);
23130b57cec5SDimitry Andric    _ForwardIterator __lm1 = _VSTD::move(_VSTD::next(__first), __last, __first);
23140b57cec5SDimitry Andric    *__lm1 = _VSTD::move(__tmp);
23150b57cec5SDimitry Andric    return __lm1;
23160b57cec5SDimitry Andric}
23170b57cec5SDimitry Andric
23180b57cec5SDimitry Andrictemplate <class _BidirectionalIterator>
23190b57cec5SDimitry Andric_BidirectionalIterator
23200b57cec5SDimitry Andric__rotate_right(_BidirectionalIterator __first, _BidirectionalIterator __last)
23210b57cec5SDimitry Andric{
23220b57cec5SDimitry Andric    typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
23230b57cec5SDimitry Andric    _BidirectionalIterator __lm1 = _VSTD::prev(__last);
23240b57cec5SDimitry Andric    value_type __tmp = _VSTD::move(*__lm1);
23250b57cec5SDimitry Andric    _BidirectionalIterator __fp1 = _VSTD::move_backward(__first, __lm1, __last);
23260b57cec5SDimitry Andric    *__first = _VSTD::move(__tmp);
23270b57cec5SDimitry Andric    return __fp1;
23280b57cec5SDimitry Andric}
23290b57cec5SDimitry Andric
23300b57cec5SDimitry Andrictemplate <class _ForwardIterator>
23310b57cec5SDimitry Andric_ForwardIterator
23320b57cec5SDimitry Andric__rotate_forward(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last)
23330b57cec5SDimitry Andric{
23340b57cec5SDimitry Andric    _ForwardIterator __i = __middle;
23350b57cec5SDimitry Andric    while (true)
23360b57cec5SDimitry Andric    {
23370b57cec5SDimitry Andric        swap(*__first, *__i);
23380b57cec5SDimitry Andric        ++__first;
23390b57cec5SDimitry Andric        if (++__i == __last)
23400b57cec5SDimitry Andric            break;
23410b57cec5SDimitry Andric        if (__first == __middle)
23420b57cec5SDimitry Andric            __middle = __i;
23430b57cec5SDimitry Andric    }
23440b57cec5SDimitry Andric    _ForwardIterator __r = __first;
23450b57cec5SDimitry Andric    if (__first != __middle)
23460b57cec5SDimitry Andric    {
23470b57cec5SDimitry Andric        __i = __middle;
23480b57cec5SDimitry Andric        while (true)
23490b57cec5SDimitry Andric        {
23500b57cec5SDimitry Andric            swap(*__first, *__i);
23510b57cec5SDimitry Andric            ++__first;
23520b57cec5SDimitry Andric            if (++__i == __last)
23530b57cec5SDimitry Andric            {
23540b57cec5SDimitry Andric                if (__first == __middle)
23550b57cec5SDimitry Andric                    break;
23560b57cec5SDimitry Andric                __i = __middle;
23570b57cec5SDimitry Andric            }
23580b57cec5SDimitry Andric            else if (__first == __middle)
23590b57cec5SDimitry Andric                __middle = __i;
23600b57cec5SDimitry Andric        }
23610b57cec5SDimitry Andric    }
23620b57cec5SDimitry Andric    return __r;
23630b57cec5SDimitry Andric}
23640b57cec5SDimitry Andric
23650b57cec5SDimitry Andrictemplate<typename _Integral>
23660b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
23670b57cec5SDimitry Andric_Integral
23680b57cec5SDimitry Andric__algo_gcd(_Integral __x, _Integral __y)
23690b57cec5SDimitry Andric{
23700b57cec5SDimitry Andric    do
23710b57cec5SDimitry Andric    {
23720b57cec5SDimitry Andric        _Integral __t = __x % __y;
23730b57cec5SDimitry Andric        __x = __y;
23740b57cec5SDimitry Andric        __y = __t;
23750b57cec5SDimitry Andric    } while (__y);
23760b57cec5SDimitry Andric    return __x;
23770b57cec5SDimitry Andric}
23780b57cec5SDimitry Andric
23790b57cec5SDimitry Andrictemplate<typename _RandomAccessIterator>
23800b57cec5SDimitry Andric_RandomAccessIterator
23810b57cec5SDimitry Andric__rotate_gcd(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last)
23820b57cec5SDimitry Andric{
23830b57cec5SDimitry Andric    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
23840b57cec5SDimitry Andric    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
23850b57cec5SDimitry Andric
23860b57cec5SDimitry Andric    const difference_type __m1 = __middle - __first;
23870b57cec5SDimitry Andric    const difference_type __m2 = __last - __middle;
23880b57cec5SDimitry Andric    if (__m1 == __m2)
23890b57cec5SDimitry Andric    {
23900b57cec5SDimitry Andric        _VSTD::swap_ranges(__first, __middle, __middle);
23910b57cec5SDimitry Andric        return __middle;
23920b57cec5SDimitry Andric    }
23930b57cec5SDimitry Andric    const difference_type __g = _VSTD::__algo_gcd(__m1, __m2);
23940b57cec5SDimitry Andric    for (_RandomAccessIterator __p = __first + __g; __p != __first;)
23950b57cec5SDimitry Andric    {
23960b57cec5SDimitry Andric        value_type __t(_VSTD::move(*--__p));
23970b57cec5SDimitry Andric        _RandomAccessIterator __p1 = __p;
23980b57cec5SDimitry Andric        _RandomAccessIterator __p2 = __p1 + __m1;
23990b57cec5SDimitry Andric        do
24000b57cec5SDimitry Andric        {
24010b57cec5SDimitry Andric            *__p1 = _VSTD::move(*__p2);
24020b57cec5SDimitry Andric            __p1 = __p2;
24030b57cec5SDimitry Andric            const difference_type __d = __last - __p2;
24040b57cec5SDimitry Andric            if (__m1 < __d)
24050b57cec5SDimitry Andric                __p2 += __m1;
24060b57cec5SDimitry Andric            else
24070b57cec5SDimitry Andric                __p2 = __first + (__m1 - __d);
24080b57cec5SDimitry Andric        } while (__p2 != __p);
24090b57cec5SDimitry Andric        *__p1 = _VSTD::move(__t);
24100b57cec5SDimitry Andric    }
24110b57cec5SDimitry Andric    return __first + __m2;
24120b57cec5SDimitry Andric}
24130b57cec5SDimitry Andric
24140b57cec5SDimitry Andrictemplate <class _ForwardIterator>
24150b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
24160b57cec5SDimitry Andric_ForwardIterator
24170b57cec5SDimitry Andric__rotate(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last,
24180b57cec5SDimitry Andric         _VSTD::forward_iterator_tag)
24190b57cec5SDimitry Andric{
24200b57cec5SDimitry Andric    typedef typename _VSTD::iterator_traits<_ForwardIterator>::value_type value_type;
24210b57cec5SDimitry Andric    if (_VSTD::is_trivially_move_assignable<value_type>::value)
24220b57cec5SDimitry Andric    {
24230b57cec5SDimitry Andric        if (_VSTD::next(__first) == __middle)
24240b57cec5SDimitry Andric            return _VSTD::__rotate_left(__first, __last);
24250b57cec5SDimitry Andric    }
24260b57cec5SDimitry Andric    return _VSTD::__rotate_forward(__first, __middle, __last);
24270b57cec5SDimitry Andric}
24280b57cec5SDimitry Andric
24290b57cec5SDimitry Andrictemplate <class _BidirectionalIterator>
24300b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
24310b57cec5SDimitry Andric_BidirectionalIterator
24320b57cec5SDimitry Andric__rotate(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last,
24330b57cec5SDimitry Andric         _VSTD::bidirectional_iterator_tag)
24340b57cec5SDimitry Andric{
24350b57cec5SDimitry Andric    typedef typename _VSTD::iterator_traits<_BidirectionalIterator>::value_type value_type;
24360b57cec5SDimitry Andric    if (_VSTD::is_trivially_move_assignable<value_type>::value)
24370b57cec5SDimitry Andric    {
24380b57cec5SDimitry Andric        if (_VSTD::next(__first) == __middle)
24390b57cec5SDimitry Andric            return _VSTD::__rotate_left(__first, __last);
24400b57cec5SDimitry Andric        if (_VSTD::next(__middle) == __last)
24410b57cec5SDimitry Andric            return _VSTD::__rotate_right(__first, __last);
24420b57cec5SDimitry Andric    }
24430b57cec5SDimitry Andric    return _VSTD::__rotate_forward(__first, __middle, __last);
24440b57cec5SDimitry Andric}
24450b57cec5SDimitry Andric
24460b57cec5SDimitry Andrictemplate <class _RandomAccessIterator>
24470b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
24480b57cec5SDimitry Andric_RandomAccessIterator
24490b57cec5SDimitry Andric__rotate(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last,
24500b57cec5SDimitry Andric         _VSTD::random_access_iterator_tag)
24510b57cec5SDimitry Andric{
24520b57cec5SDimitry Andric    typedef typename _VSTD::iterator_traits<_RandomAccessIterator>::value_type value_type;
24530b57cec5SDimitry Andric    if (_VSTD::is_trivially_move_assignable<value_type>::value)
24540b57cec5SDimitry Andric    {
24550b57cec5SDimitry Andric        if (_VSTD::next(__first) == __middle)
24560b57cec5SDimitry Andric            return _VSTD::__rotate_left(__first, __last);
24570b57cec5SDimitry Andric        if (_VSTD::next(__middle) == __last)
24580b57cec5SDimitry Andric            return _VSTD::__rotate_right(__first, __last);
24590b57cec5SDimitry Andric        return _VSTD::__rotate_gcd(__first, __middle, __last);
24600b57cec5SDimitry Andric    }
24610b57cec5SDimitry Andric    return _VSTD::__rotate_forward(__first, __middle, __last);
24620b57cec5SDimitry Andric}
24630b57cec5SDimitry Andric
24640b57cec5SDimitry Andrictemplate <class _ForwardIterator>
24650b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
24660b57cec5SDimitry Andric_ForwardIterator
24670b57cec5SDimitry Andricrotate(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last)
24680b57cec5SDimitry Andric{
24690b57cec5SDimitry Andric    if (__first == __middle)
24700b57cec5SDimitry Andric        return __last;
24710b57cec5SDimitry Andric    if (__middle == __last)
24720b57cec5SDimitry Andric        return __first;
24730b57cec5SDimitry Andric    return _VSTD::__rotate(__first, __middle, __last,
24740b57cec5SDimitry Andric                           typename _VSTD::iterator_traits<_ForwardIterator>::iterator_category());
24750b57cec5SDimitry Andric}
24760b57cec5SDimitry Andric
24770b57cec5SDimitry Andric// rotate_copy
24780b57cec5SDimitry Andric
24790b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _OutputIterator>
24800b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
24810b57cec5SDimitry Andric_OutputIterator
24820b57cec5SDimitry Andricrotate_copy(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last, _OutputIterator __result)
24830b57cec5SDimitry Andric{
24840b57cec5SDimitry Andric    return _VSTD::copy(__first, __middle, _VSTD::copy(__middle, __last, __result));
24850b57cec5SDimitry Andric}
24860b57cec5SDimitry Andric
24870b57cec5SDimitry Andric// min_element
24880b57cec5SDimitry Andric
24890b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Compare>
24900b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
24910b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
24920b57cec5SDimitry Andric_ForwardIterator
24930b57cec5SDimitry Andricmin_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
24940b57cec5SDimitry Andric{
24950b57cec5SDimitry Andric    static_assert(__is_forward_iterator<_ForwardIterator>::value,
24960b57cec5SDimitry Andric        "std::min_element requires a ForwardIterator");
24970b57cec5SDimitry Andric    if (__first != __last)
24980b57cec5SDimitry Andric    {
24990b57cec5SDimitry Andric        _ForwardIterator __i = __first;
25000b57cec5SDimitry Andric        while (++__i != __last)
25010b57cec5SDimitry Andric            if (__comp(*__i, *__first))
25020b57cec5SDimitry Andric                __first = __i;
25030b57cec5SDimitry Andric    }
25040b57cec5SDimitry Andric    return __first;
25050b57cec5SDimitry Andric}
25060b57cec5SDimitry Andric
25070b57cec5SDimitry Andrictemplate <class _ForwardIterator>
25080b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
25090b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25100b57cec5SDimitry Andric_ForwardIterator
25110b57cec5SDimitry Andricmin_element(_ForwardIterator __first, _ForwardIterator __last)
25120b57cec5SDimitry Andric{
25130b57cec5SDimitry Andric    return _VSTD::min_element(__first, __last,
25140b57cec5SDimitry Andric              __less<typename iterator_traits<_ForwardIterator>::value_type>());
25150b57cec5SDimitry Andric}
25160b57cec5SDimitry Andric
25170b57cec5SDimitry Andric// min
25180b57cec5SDimitry Andric
25190b57cec5SDimitry Andrictemplate <class _Tp, class _Compare>
25200b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
25210b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25220b57cec5SDimitry Andricconst _Tp&
25230b57cec5SDimitry Andricmin(const _Tp& __a, const _Tp& __b, _Compare __comp)
25240b57cec5SDimitry Andric{
25250b57cec5SDimitry Andric    return __comp(__b, __a) ? __b : __a;
25260b57cec5SDimitry Andric}
25270b57cec5SDimitry Andric
25280b57cec5SDimitry Andrictemplate <class _Tp>
25290b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
25300b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25310b57cec5SDimitry Andricconst _Tp&
25320b57cec5SDimitry Andricmin(const _Tp& __a, const _Tp& __b)
25330b57cec5SDimitry Andric{
25340b57cec5SDimitry Andric    return _VSTD::min(__a, __b, __less<_Tp>());
25350b57cec5SDimitry Andric}
25360b57cec5SDimitry Andric
25370b57cec5SDimitry Andric#ifndef _LIBCPP_CXX03_LANG
25380b57cec5SDimitry Andric
25390b57cec5SDimitry Andrictemplate<class _Tp, class _Compare>
25400b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
25410b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25420b57cec5SDimitry Andric_Tp
25430b57cec5SDimitry Andricmin(initializer_list<_Tp> __t, _Compare __comp)
25440b57cec5SDimitry Andric{
25450b57cec5SDimitry Andric    return *_VSTD::min_element(__t.begin(), __t.end(), __comp);
25460b57cec5SDimitry Andric}
25470b57cec5SDimitry Andric
25480b57cec5SDimitry Andrictemplate<class _Tp>
25490b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
25500b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25510b57cec5SDimitry Andric_Tp
25520b57cec5SDimitry Andricmin(initializer_list<_Tp> __t)
25530b57cec5SDimitry Andric{
25540b57cec5SDimitry Andric    return *_VSTD::min_element(__t.begin(), __t.end(), __less<_Tp>());
25550b57cec5SDimitry Andric}
25560b57cec5SDimitry Andric
25570b57cec5SDimitry Andric#endif  // _LIBCPP_CXX03_LANG
25580b57cec5SDimitry Andric
25590b57cec5SDimitry Andric// max_element
25600b57cec5SDimitry Andric
25610b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Compare>
25620b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
25630b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25640b57cec5SDimitry Andric_ForwardIterator
25650b57cec5SDimitry Andricmax_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
25660b57cec5SDimitry Andric{
25670b57cec5SDimitry Andric    static_assert(__is_forward_iterator<_ForwardIterator>::value,
25680b57cec5SDimitry Andric        "std::max_element requires a ForwardIterator");
25690b57cec5SDimitry Andric    if (__first != __last)
25700b57cec5SDimitry Andric    {
25710b57cec5SDimitry Andric        _ForwardIterator __i = __first;
25720b57cec5SDimitry Andric        while (++__i != __last)
25730b57cec5SDimitry Andric            if (__comp(*__first, *__i))
25740b57cec5SDimitry Andric                __first = __i;
25750b57cec5SDimitry Andric    }
25760b57cec5SDimitry Andric    return __first;
25770b57cec5SDimitry Andric}
25780b57cec5SDimitry Andric
25790b57cec5SDimitry Andric
25800b57cec5SDimitry Andrictemplate <class _ForwardIterator>
25810b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
25820b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25830b57cec5SDimitry Andric_ForwardIterator
25840b57cec5SDimitry Andricmax_element(_ForwardIterator __first, _ForwardIterator __last)
25850b57cec5SDimitry Andric{
25860b57cec5SDimitry Andric    return _VSTD::max_element(__first, __last,
25870b57cec5SDimitry Andric              __less<typename iterator_traits<_ForwardIterator>::value_type>());
25880b57cec5SDimitry Andric}
25890b57cec5SDimitry Andric
25900b57cec5SDimitry Andric// max
25910b57cec5SDimitry Andric
25920b57cec5SDimitry Andrictemplate <class _Tp, class _Compare>
25930b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
25940b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25950b57cec5SDimitry Andricconst _Tp&
25960b57cec5SDimitry Andricmax(const _Tp& __a, const _Tp& __b, _Compare __comp)
25970b57cec5SDimitry Andric{
25980b57cec5SDimitry Andric    return __comp(__a, __b) ? __b : __a;
25990b57cec5SDimitry Andric}
26000b57cec5SDimitry Andric
26010b57cec5SDimitry Andrictemplate <class _Tp>
26020b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
26030b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
26040b57cec5SDimitry Andricconst _Tp&
26050b57cec5SDimitry Andricmax(const _Tp& __a, const _Tp& __b)
26060b57cec5SDimitry Andric{
26070b57cec5SDimitry Andric    return _VSTD::max(__a, __b, __less<_Tp>());
26080b57cec5SDimitry Andric}
26090b57cec5SDimitry Andric
26100b57cec5SDimitry Andric#ifndef _LIBCPP_CXX03_LANG
26110b57cec5SDimitry Andric
26120b57cec5SDimitry Andrictemplate<class _Tp, class _Compare>
26130b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
26140b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
26150b57cec5SDimitry Andric_Tp
26160b57cec5SDimitry Andricmax(initializer_list<_Tp> __t, _Compare __comp)
26170b57cec5SDimitry Andric{
26180b57cec5SDimitry Andric    return *_VSTD::max_element(__t.begin(), __t.end(), __comp);
26190b57cec5SDimitry Andric}
26200b57cec5SDimitry Andric
26210b57cec5SDimitry Andrictemplate<class _Tp>
26220b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
26230b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
26240b57cec5SDimitry Andric_Tp
26250b57cec5SDimitry Andricmax(initializer_list<_Tp> __t)
26260b57cec5SDimitry Andric{
26270b57cec5SDimitry Andric    return *_VSTD::max_element(__t.begin(), __t.end(), __less<_Tp>());
26280b57cec5SDimitry Andric}
26290b57cec5SDimitry Andric
26300b57cec5SDimitry Andric#endif  // _LIBCPP_CXX03_LANG
26310b57cec5SDimitry Andric
26320b57cec5SDimitry Andric#if _LIBCPP_STD_VER > 14
26330b57cec5SDimitry Andric// clamp
26340b57cec5SDimitry Andrictemplate<class _Tp, class _Compare>
26350b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
26360b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
26370b57cec5SDimitry Andricconst _Tp&
26380b57cec5SDimitry Andricclamp(const _Tp& __v, const _Tp& __lo, const _Tp& __hi, _Compare __comp)
26390b57cec5SDimitry Andric{
26400b57cec5SDimitry Andric    _LIBCPP_ASSERT(!__comp(__hi, __lo), "Bad bounds passed to std::clamp");
26410b57cec5SDimitry Andric    return __comp(__v, __lo) ? __lo : __comp(__hi, __v) ? __hi : __v;
26420b57cec5SDimitry Andric
26430b57cec5SDimitry Andric}
26440b57cec5SDimitry Andric
26450b57cec5SDimitry Andrictemplate<class _Tp>
26460b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
26470b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
26480b57cec5SDimitry Andricconst _Tp&
26490b57cec5SDimitry Andricclamp(const _Tp& __v, const _Tp& __lo, const _Tp& __hi)
26500b57cec5SDimitry Andric{
26510b57cec5SDimitry Andric    return _VSTD::clamp(__v, __lo, __hi, __less<_Tp>());
26520b57cec5SDimitry Andric}
26530b57cec5SDimitry Andric#endif
26540b57cec5SDimitry Andric
26550b57cec5SDimitry Andric// minmax_element
26560b57cec5SDimitry Andric
26570b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Compare>
26580b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX11
26590b57cec5SDimitry Andricstd::pair<_ForwardIterator, _ForwardIterator>
26600b57cec5SDimitry Andricminmax_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
26610b57cec5SDimitry Andric{
26620b57cec5SDimitry Andric  static_assert(__is_forward_iterator<_ForwardIterator>::value,
26630b57cec5SDimitry Andric        "std::minmax_element requires a ForwardIterator");
26640b57cec5SDimitry Andric  std::pair<_ForwardIterator, _ForwardIterator> __result(__first, __first);
26650b57cec5SDimitry Andric  if (__first != __last)
26660b57cec5SDimitry Andric  {
26670b57cec5SDimitry Andric      if (++__first != __last)
26680b57cec5SDimitry Andric      {
26690b57cec5SDimitry Andric          if (__comp(*__first, *__result.first))
26700b57cec5SDimitry Andric              __result.first = __first;
26710b57cec5SDimitry Andric          else
26720b57cec5SDimitry Andric              __result.second = __first;
26730b57cec5SDimitry Andric          while (++__first != __last)
26740b57cec5SDimitry Andric          {
26750b57cec5SDimitry Andric              _ForwardIterator __i = __first;
26760b57cec5SDimitry Andric              if (++__first == __last)
26770b57cec5SDimitry Andric              {
26780b57cec5SDimitry Andric                  if (__comp(*__i, *__result.first))
26790b57cec5SDimitry Andric                      __result.first = __i;
26800b57cec5SDimitry Andric                  else if (!__comp(*__i, *__result.second))
26810b57cec5SDimitry Andric                      __result.second = __i;
26820b57cec5SDimitry Andric                  break;
26830b57cec5SDimitry Andric              }
26840b57cec5SDimitry Andric              else
26850b57cec5SDimitry Andric              {
26860b57cec5SDimitry Andric                  if (__comp(*__first, *__i))
26870b57cec5SDimitry Andric                  {
26880b57cec5SDimitry Andric                      if (__comp(*__first, *__result.first))
26890b57cec5SDimitry Andric                          __result.first = __first;
26900b57cec5SDimitry Andric                      if (!__comp(*__i, *__result.second))
26910b57cec5SDimitry Andric                          __result.second = __i;
26920b57cec5SDimitry Andric                  }
26930b57cec5SDimitry Andric                  else
26940b57cec5SDimitry Andric                  {
26950b57cec5SDimitry Andric                      if (__comp(*__i, *__result.first))
26960b57cec5SDimitry Andric                          __result.first = __i;
26970b57cec5SDimitry Andric                      if (!__comp(*__first, *__result.second))
26980b57cec5SDimitry Andric                          __result.second = __first;
26990b57cec5SDimitry Andric                  }
27000b57cec5SDimitry Andric              }
27010b57cec5SDimitry Andric          }
27020b57cec5SDimitry Andric      }
27030b57cec5SDimitry Andric  }
27040b57cec5SDimitry Andric  return __result;
27050b57cec5SDimitry Andric}
27060b57cec5SDimitry Andric
27070b57cec5SDimitry Andrictemplate <class _ForwardIterator>
27080b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
27090b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
27100b57cec5SDimitry Andricstd::pair<_ForwardIterator, _ForwardIterator>
27110b57cec5SDimitry Andricminmax_element(_ForwardIterator __first, _ForwardIterator __last)
27120b57cec5SDimitry Andric{
27130b57cec5SDimitry Andric    return _VSTD::minmax_element(__first, __last,
27140b57cec5SDimitry Andric              __less<typename iterator_traits<_ForwardIterator>::value_type>());
27150b57cec5SDimitry Andric}
27160b57cec5SDimitry Andric
27170b57cec5SDimitry Andric// minmax
27180b57cec5SDimitry Andric
27190b57cec5SDimitry Andrictemplate<class _Tp, class _Compare>
27200b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
27210b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
27220b57cec5SDimitry Andricpair<const _Tp&, const _Tp&>
27230b57cec5SDimitry Andricminmax(const _Tp& __a, const _Tp& __b, _Compare __comp)
27240b57cec5SDimitry Andric{
27250b57cec5SDimitry Andric    return __comp(__b, __a) ? pair<const _Tp&, const _Tp&>(__b, __a) :
27260b57cec5SDimitry Andric                              pair<const _Tp&, const _Tp&>(__a, __b);
27270b57cec5SDimitry Andric}
27280b57cec5SDimitry Andric
27290b57cec5SDimitry Andrictemplate<class _Tp>
27300b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
27310b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
27320b57cec5SDimitry Andricpair<const _Tp&, const _Tp&>
27330b57cec5SDimitry Andricminmax(const _Tp& __a, const _Tp& __b)
27340b57cec5SDimitry Andric{
27350b57cec5SDimitry Andric    return _VSTD::minmax(__a, __b, __less<_Tp>());
27360b57cec5SDimitry Andric}
27370b57cec5SDimitry Andric
27380b57cec5SDimitry Andric#ifndef _LIBCPP_CXX03_LANG
27390b57cec5SDimitry Andric
27400b57cec5SDimitry Andrictemplate<class _Tp, class _Compare>
27410b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
27420b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
27430b57cec5SDimitry Andricpair<_Tp, _Tp>
27440b57cec5SDimitry Andricminmax(initializer_list<_Tp> __t, _Compare __comp)
27450b57cec5SDimitry Andric{
27460b57cec5SDimitry Andric    typedef typename initializer_list<_Tp>::const_iterator _Iter;
27470b57cec5SDimitry Andric    _Iter __first = __t.begin();
27480b57cec5SDimitry Andric    _Iter __last  = __t.end();
27490b57cec5SDimitry Andric    std::pair<_Tp, _Tp> __result(*__first, *__first);
27500b57cec5SDimitry Andric
27510b57cec5SDimitry Andric    ++__first;
27520b57cec5SDimitry Andric    if (__t.size() % 2 == 0)
27530b57cec5SDimitry Andric    {
27540b57cec5SDimitry Andric        if (__comp(*__first,  __result.first))
27550b57cec5SDimitry Andric            __result.first  = *__first;
27560b57cec5SDimitry Andric        else
27570b57cec5SDimitry Andric            __result.second = *__first;
27580b57cec5SDimitry Andric        ++__first;
27590b57cec5SDimitry Andric    }
27600b57cec5SDimitry Andric
27610b57cec5SDimitry Andric    while (__first != __last)
27620b57cec5SDimitry Andric    {
27630b57cec5SDimitry Andric        _Tp __prev = *__first++;
27640b57cec5SDimitry Andric        if (__comp(*__first, __prev)) {
27650b57cec5SDimitry Andric            if ( __comp(*__first, __result.first)) __result.first  = *__first;
27660b57cec5SDimitry Andric            if (!__comp(__prev, __result.second))  __result.second = __prev;
27670b57cec5SDimitry Andric            }
27680b57cec5SDimitry Andric        else {
27690b57cec5SDimitry Andric            if ( __comp(__prev, __result.first))    __result.first  = __prev;
27700b57cec5SDimitry Andric            if (!__comp(*__first, __result.second)) __result.second = *__first;
27710b57cec5SDimitry Andric            }
27720b57cec5SDimitry Andric
27730b57cec5SDimitry Andric        __first++;
27740b57cec5SDimitry Andric    }
27750b57cec5SDimitry Andric    return __result;
27760b57cec5SDimitry Andric}
27770b57cec5SDimitry Andric
27780b57cec5SDimitry Andrictemplate<class _Tp>
27790b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
27800b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
27810b57cec5SDimitry Andricpair<_Tp, _Tp>
27820b57cec5SDimitry Andricminmax(initializer_list<_Tp> __t)
27830b57cec5SDimitry Andric{
27840b57cec5SDimitry Andric    return _VSTD::minmax(__t, __less<_Tp>());
27850b57cec5SDimitry Andric}
27860b57cec5SDimitry Andric
27870b57cec5SDimitry Andric#endif  // _LIBCPP_CXX03_LANG
27880b57cec5SDimitry Andric
27890b57cec5SDimitry Andric// random_shuffle
27900b57cec5SDimitry Andric
27910b57cec5SDimitry Andric// __independent_bits_engine
27920b57cec5SDimitry Andric
27930b57cec5SDimitry Andrictemplate <unsigned long long _Xp, size_t _Rp>
27940b57cec5SDimitry Andricstruct __log2_imp
27950b57cec5SDimitry Andric{
27960b57cec5SDimitry Andric    static const size_t value = _Xp & ((unsigned long long)(1) << _Rp) ? _Rp
27970b57cec5SDimitry Andric                                           : __log2_imp<_Xp, _Rp - 1>::value;
27980b57cec5SDimitry Andric};
27990b57cec5SDimitry Andric
28000b57cec5SDimitry Andrictemplate <unsigned long long _Xp>
28010b57cec5SDimitry Andricstruct __log2_imp<_Xp, 0>
28020b57cec5SDimitry Andric{
28030b57cec5SDimitry Andric    static const size_t value = 0;
28040b57cec5SDimitry Andric};
28050b57cec5SDimitry Andric
28060b57cec5SDimitry Andrictemplate <size_t _Rp>
28070b57cec5SDimitry Andricstruct __log2_imp<0, _Rp>
28080b57cec5SDimitry Andric{
28090b57cec5SDimitry Andric    static const size_t value = _Rp + 1;
28100b57cec5SDimitry Andric};
28110b57cec5SDimitry Andric
28120b57cec5SDimitry Andrictemplate <class _UIntType, _UIntType _Xp>
28130b57cec5SDimitry Andricstruct __log2
28140b57cec5SDimitry Andric{
28150b57cec5SDimitry Andric    static const size_t value = __log2_imp<_Xp,
28160b57cec5SDimitry Andric                                         sizeof(_UIntType) * __CHAR_BIT__ - 1>::value;
28170b57cec5SDimitry Andric};
28180b57cec5SDimitry Andric
28190b57cec5SDimitry Andrictemplate<class _Engine, class _UIntType>
28200b57cec5SDimitry Andricclass __independent_bits_engine
28210b57cec5SDimitry Andric{
28220b57cec5SDimitry Andricpublic:
28230b57cec5SDimitry Andric    // types
28240b57cec5SDimitry Andric    typedef _UIntType result_type;
28250b57cec5SDimitry Andric
28260b57cec5SDimitry Andricprivate:
28270b57cec5SDimitry Andric    typedef typename _Engine::result_type _Engine_result_type;
28280b57cec5SDimitry Andric    typedef typename conditional
28290b57cec5SDimitry Andric        <
28300b57cec5SDimitry Andric            sizeof(_Engine_result_type) <= sizeof(result_type),
28310b57cec5SDimitry Andric                result_type,
28320b57cec5SDimitry Andric                _Engine_result_type
28330b57cec5SDimitry Andric        >::type _Working_result_type;
28340b57cec5SDimitry Andric
28350b57cec5SDimitry Andric    _Engine& __e_;
28360b57cec5SDimitry Andric    size_t __w_;
28370b57cec5SDimitry Andric    size_t __w0_;
28380b57cec5SDimitry Andric    size_t __n_;
28390b57cec5SDimitry Andric    size_t __n0_;
28400b57cec5SDimitry Andric    _Working_result_type __y0_;
28410b57cec5SDimitry Andric    _Working_result_type __y1_;
28420b57cec5SDimitry Andric    _Engine_result_type __mask0_;
28430b57cec5SDimitry Andric    _Engine_result_type __mask1_;
28440b57cec5SDimitry Andric
28450b57cec5SDimitry Andric#ifdef _LIBCPP_CXX03_LANG
28460b57cec5SDimitry Andric    static const _Working_result_type _Rp = _Engine::_Max - _Engine::_Min
28470b57cec5SDimitry Andric                                          + _Working_result_type(1);
28480b57cec5SDimitry Andric#else
28490b57cec5SDimitry Andric    static _LIBCPP_CONSTEXPR const _Working_result_type _Rp = _Engine::max() - _Engine::min()
28500b57cec5SDimitry Andric                                                      + _Working_result_type(1);
28510b57cec5SDimitry Andric#endif
28520b57cec5SDimitry Andric    static _LIBCPP_CONSTEXPR const size_t __m = __log2<_Working_result_type, _Rp>::value;
28530b57cec5SDimitry Andric    static _LIBCPP_CONSTEXPR const size_t _WDt = numeric_limits<_Working_result_type>::digits;
28540b57cec5SDimitry Andric    static _LIBCPP_CONSTEXPR const size_t _EDt = numeric_limits<_Engine_result_type>::digits;
28550b57cec5SDimitry Andric
28560b57cec5SDimitry Andricpublic:
28570b57cec5SDimitry Andric    // constructors and seeding functions
28580b57cec5SDimitry Andric    __independent_bits_engine(_Engine& __e, size_t __w);
28590b57cec5SDimitry Andric
28600b57cec5SDimitry Andric    // generating functions
28610b57cec5SDimitry Andric    result_type operator()() {return __eval(integral_constant<bool, _Rp != 0>());}
28620b57cec5SDimitry Andric
28630b57cec5SDimitry Andricprivate:
28640b57cec5SDimitry Andric    result_type __eval(false_type);
28650b57cec5SDimitry Andric    result_type __eval(true_type);
28660b57cec5SDimitry Andric};
28670b57cec5SDimitry Andric
28680b57cec5SDimitry Andrictemplate<class _Engine, class _UIntType>
28690b57cec5SDimitry Andric__independent_bits_engine<_Engine, _UIntType>
28700b57cec5SDimitry Andric    ::__independent_bits_engine(_Engine& __e, size_t __w)
28710b57cec5SDimitry Andric        : __e_(__e),
28720b57cec5SDimitry Andric          __w_(__w)
28730b57cec5SDimitry Andric{
28740b57cec5SDimitry Andric    __n_ = __w_ / __m + (__w_ % __m != 0);
28750b57cec5SDimitry Andric    __w0_ = __w_ / __n_;
28760b57cec5SDimitry Andric    if (_Rp == 0)
28770b57cec5SDimitry Andric        __y0_ = _Rp;
28780b57cec5SDimitry Andric    else if (__w0_ < _WDt)
28790b57cec5SDimitry Andric        __y0_ = (_Rp >> __w0_) << __w0_;
28800b57cec5SDimitry Andric    else
28810b57cec5SDimitry Andric        __y0_ = 0;
28820b57cec5SDimitry Andric    if (_Rp - __y0_ > __y0_ / __n_)
28830b57cec5SDimitry Andric    {
28840b57cec5SDimitry Andric        ++__n_;
28850b57cec5SDimitry Andric        __w0_ = __w_ / __n_;
28860b57cec5SDimitry Andric        if (__w0_ < _WDt)
28870b57cec5SDimitry Andric            __y0_ = (_Rp >> __w0_) << __w0_;
28880b57cec5SDimitry Andric        else
28890b57cec5SDimitry Andric            __y0_ = 0;
28900b57cec5SDimitry Andric    }
28910b57cec5SDimitry Andric    __n0_ = __n_ - __w_ % __n_;
28920b57cec5SDimitry Andric    if (__w0_ < _WDt - 1)
28930b57cec5SDimitry Andric        __y1_ = (_Rp >> (__w0_ + 1)) << (__w0_ + 1);
28940b57cec5SDimitry Andric    else
28950b57cec5SDimitry Andric        __y1_ = 0;
28960b57cec5SDimitry Andric    __mask0_ = __w0_ > 0 ? _Engine_result_type(~0) >> (_EDt - __w0_) :
28970b57cec5SDimitry Andric                          _Engine_result_type(0);
28980b57cec5SDimitry Andric    __mask1_ = __w0_ < _EDt - 1 ?
28990b57cec5SDimitry Andric                               _Engine_result_type(~0) >> (_EDt - (__w0_ + 1)) :
29000b57cec5SDimitry Andric                               _Engine_result_type(~0);
29010b57cec5SDimitry Andric}
29020b57cec5SDimitry Andric
29030b57cec5SDimitry Andrictemplate<class _Engine, class _UIntType>
29040b57cec5SDimitry Andricinline
29050b57cec5SDimitry Andric_UIntType
29060b57cec5SDimitry Andric__independent_bits_engine<_Engine, _UIntType>::__eval(false_type)
29070b57cec5SDimitry Andric{
29080b57cec5SDimitry Andric    return static_cast<result_type>(__e_() & __mask0_);
29090b57cec5SDimitry Andric}
29100b57cec5SDimitry Andric
29110b57cec5SDimitry Andrictemplate<class _Engine, class _UIntType>
29120b57cec5SDimitry Andric_UIntType
29130b57cec5SDimitry Andric__independent_bits_engine<_Engine, _UIntType>::__eval(true_type)
29140b57cec5SDimitry Andric{
29150b57cec5SDimitry Andric    const size_t _WRt = numeric_limits<result_type>::digits;
29160b57cec5SDimitry Andric    result_type _Sp = 0;
29170b57cec5SDimitry Andric    for (size_t __k = 0; __k < __n0_; ++__k)
29180b57cec5SDimitry Andric    {
29190b57cec5SDimitry Andric        _Engine_result_type __u;
29200b57cec5SDimitry Andric        do
29210b57cec5SDimitry Andric        {
29220b57cec5SDimitry Andric            __u = __e_() - _Engine::min();
29230b57cec5SDimitry Andric        } while (__u >= __y0_);
29240b57cec5SDimitry Andric        if (__w0_ < _WRt)
29250b57cec5SDimitry Andric            _Sp <<= __w0_;
29260b57cec5SDimitry Andric        else
29270b57cec5SDimitry Andric            _Sp = 0;
29280b57cec5SDimitry Andric        _Sp += __u & __mask0_;
29290b57cec5SDimitry Andric    }
29300b57cec5SDimitry Andric    for (size_t __k = __n0_; __k < __n_; ++__k)
29310b57cec5SDimitry Andric    {
29320b57cec5SDimitry Andric        _Engine_result_type __u;
29330b57cec5SDimitry Andric        do
29340b57cec5SDimitry Andric        {
29350b57cec5SDimitry Andric            __u = __e_() - _Engine::min();
29360b57cec5SDimitry Andric        } while (__u >= __y1_);
29370b57cec5SDimitry Andric        if (__w0_ < _WRt - 1)
29380b57cec5SDimitry Andric            _Sp <<= __w0_ + 1;
29390b57cec5SDimitry Andric        else
29400b57cec5SDimitry Andric            _Sp = 0;
29410b57cec5SDimitry Andric        _Sp += __u & __mask1_;
29420b57cec5SDimitry Andric    }
29430b57cec5SDimitry Andric    return _Sp;
29440b57cec5SDimitry Andric}
29450b57cec5SDimitry Andric
29460b57cec5SDimitry Andric// uniform_int_distribution
29470b57cec5SDimitry Andric
29480b57cec5SDimitry Andrictemplate<class _IntType = int>
29490b57cec5SDimitry Andricclass uniform_int_distribution
29500b57cec5SDimitry Andric{
29510b57cec5SDimitry Andricpublic:
29520b57cec5SDimitry Andric    // types
29530b57cec5SDimitry Andric    typedef _IntType result_type;
29540b57cec5SDimitry Andric
29550b57cec5SDimitry Andric    class param_type
29560b57cec5SDimitry Andric    {
29570b57cec5SDimitry Andric        result_type __a_;
29580b57cec5SDimitry Andric        result_type __b_;
29590b57cec5SDimitry Andric    public:
29600b57cec5SDimitry Andric        typedef uniform_int_distribution distribution_type;
29610b57cec5SDimitry Andric
29620b57cec5SDimitry Andric        explicit param_type(result_type __a = 0,
29630b57cec5SDimitry Andric                            result_type __b = numeric_limits<result_type>::max())
29640b57cec5SDimitry Andric            : __a_(__a), __b_(__b) {}
29650b57cec5SDimitry Andric
29660b57cec5SDimitry Andric        result_type a() const {return __a_;}
29670b57cec5SDimitry Andric        result_type b() const {return __b_;}
29680b57cec5SDimitry Andric
29690b57cec5SDimitry Andric        friend bool operator==(const param_type& __x, const param_type& __y)
29700b57cec5SDimitry Andric            {return __x.__a_ == __y.__a_ && __x.__b_ == __y.__b_;}
29710b57cec5SDimitry Andric        friend bool operator!=(const param_type& __x, const param_type& __y)
29720b57cec5SDimitry Andric            {return !(__x == __y);}
29730b57cec5SDimitry Andric    };
29740b57cec5SDimitry Andric
29750b57cec5SDimitry Andricprivate:
29760b57cec5SDimitry Andric    param_type __p_;
29770b57cec5SDimitry Andric
29780b57cec5SDimitry Andricpublic:
29790b57cec5SDimitry Andric    // constructors and reset functions
29800b57cec5SDimitry Andric    explicit uniform_int_distribution(result_type __a = 0,
29810b57cec5SDimitry Andric                                      result_type __b = numeric_limits<result_type>::max())
29820b57cec5SDimitry Andric        : __p_(param_type(__a, __b)) {}
29830b57cec5SDimitry Andric    explicit uniform_int_distribution(const param_type& __p) : __p_(__p) {}
29840b57cec5SDimitry Andric    void reset() {}
29850b57cec5SDimitry Andric
29860b57cec5SDimitry Andric    // generating functions
29870b57cec5SDimitry Andric    template<class _URNG> result_type operator()(_URNG& __g)
29880b57cec5SDimitry Andric        {return (*this)(__g, __p_);}
29890b57cec5SDimitry Andric    template<class _URNG> result_type operator()(_URNG& __g, const param_type& __p);
29900b57cec5SDimitry Andric
29910b57cec5SDimitry Andric    // property functions
29920b57cec5SDimitry Andric    result_type a() const {return __p_.a();}
29930b57cec5SDimitry Andric    result_type b() const {return __p_.b();}
29940b57cec5SDimitry Andric
29950b57cec5SDimitry Andric    param_type param() const {return __p_;}
29960b57cec5SDimitry Andric    void param(const param_type& __p) {__p_ = __p;}
29970b57cec5SDimitry Andric
29980b57cec5SDimitry Andric    result_type min() const {return a();}
29990b57cec5SDimitry Andric    result_type max() const {return b();}
30000b57cec5SDimitry Andric
30010b57cec5SDimitry Andric    friend bool operator==(const uniform_int_distribution& __x,
30020b57cec5SDimitry Andric                           const uniform_int_distribution& __y)
30030b57cec5SDimitry Andric        {return __x.__p_ == __y.__p_;}
30040b57cec5SDimitry Andric    friend bool operator!=(const uniform_int_distribution& __x,
30050b57cec5SDimitry Andric                           const uniform_int_distribution& __y)
30060b57cec5SDimitry Andric            {return !(__x == __y);}
30070b57cec5SDimitry Andric};
30080b57cec5SDimitry Andric
30090b57cec5SDimitry Andrictemplate<class _IntType>
30100b57cec5SDimitry Andrictemplate<class _URNG>
30110b57cec5SDimitry Andrictypename uniform_int_distribution<_IntType>::result_type
30120b57cec5SDimitry Andricuniform_int_distribution<_IntType>::operator()(_URNG& __g, const param_type& __p)
30130b57cec5SDimitry Andric_LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK
30140b57cec5SDimitry Andric{
30150b57cec5SDimitry Andric    typedef typename conditional<sizeof(result_type) <= sizeof(uint32_t),
30160b57cec5SDimitry Andric                                            uint32_t, uint64_t>::type _UIntType;
30170b57cec5SDimitry Andric    const _UIntType _Rp = _UIntType(__p.b()) - _UIntType(__p.a()) + _UIntType(1);
30180b57cec5SDimitry Andric    if (_Rp == 1)
30190b57cec5SDimitry Andric        return __p.a();
30200b57cec5SDimitry Andric    const size_t _Dt = numeric_limits<_UIntType>::digits;
30210b57cec5SDimitry Andric    typedef __independent_bits_engine<_URNG, _UIntType> _Eng;
30220b57cec5SDimitry Andric    if (_Rp == 0)
30230b57cec5SDimitry Andric        return static_cast<result_type>(_Eng(__g, _Dt)());
30240b57cec5SDimitry Andric    size_t __w = _Dt - __libcpp_clz(_Rp) - 1;
30250b57cec5SDimitry Andric    if ((_Rp & (std::numeric_limits<_UIntType>::max() >> (_Dt - __w))) != 0)
30260b57cec5SDimitry Andric        ++__w;
30270b57cec5SDimitry Andric    _Eng __e(__g, __w);
30280b57cec5SDimitry Andric    _UIntType __u;
30290b57cec5SDimitry Andric    do
30300b57cec5SDimitry Andric    {
30310b57cec5SDimitry Andric        __u = __e();
30320b57cec5SDimitry Andric    } while (__u >= _Rp);
30330b57cec5SDimitry Andric    return static_cast<result_type>(__u + __p.a());
30340b57cec5SDimitry Andric}
30350b57cec5SDimitry Andric
30360b57cec5SDimitry Andric#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_RANDOM_SHUFFLE) \
30370b57cec5SDimitry Andric  || defined(_LIBCPP_BUILDING_LIBRARY)
30380b57cec5SDimitry Andricclass _LIBCPP_TYPE_VIS __rs_default;
30390b57cec5SDimitry Andric
30400b57cec5SDimitry Andric_LIBCPP_FUNC_VIS __rs_default __rs_get();
30410b57cec5SDimitry Andric
30420b57cec5SDimitry Andricclass _LIBCPP_TYPE_VIS __rs_default
30430b57cec5SDimitry Andric{
30440b57cec5SDimitry Andric    static unsigned __c_;
30450b57cec5SDimitry Andric
30460b57cec5SDimitry Andric    __rs_default();
30470b57cec5SDimitry Andricpublic:
30480b57cec5SDimitry Andric    typedef uint_fast32_t result_type;
30490b57cec5SDimitry Andric
30500b57cec5SDimitry Andric    static const result_type _Min = 0;
30510b57cec5SDimitry Andric    static const result_type _Max = 0xFFFFFFFF;
30520b57cec5SDimitry Andric
30530b57cec5SDimitry Andric    __rs_default(const __rs_default&);
30540b57cec5SDimitry Andric    ~__rs_default();
30550b57cec5SDimitry Andric
30560b57cec5SDimitry Andric    result_type operator()();
30570b57cec5SDimitry Andric
30580b57cec5SDimitry Andric    static _LIBCPP_CONSTEXPR result_type min() {return _Min;}
30590b57cec5SDimitry Andric    static _LIBCPP_CONSTEXPR result_type max() {return _Max;}
30600b57cec5SDimitry Andric
30610b57cec5SDimitry Andric    friend _LIBCPP_FUNC_VIS __rs_default __rs_get();
30620b57cec5SDimitry Andric};
30630b57cec5SDimitry Andric
30640b57cec5SDimitry Andric_LIBCPP_FUNC_VIS __rs_default __rs_get();
30650b57cec5SDimitry Andric
30660b57cec5SDimitry Andrictemplate <class _RandomAccessIterator>
30670b57cec5SDimitry Andric_LIBCPP_DEPRECATED_IN_CXX14 void
30680b57cec5SDimitry Andricrandom_shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last)
30690b57cec5SDimitry Andric{
30700b57cec5SDimitry Andric    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
30710b57cec5SDimitry Andric    typedef uniform_int_distribution<ptrdiff_t> _Dp;
30720b57cec5SDimitry Andric    typedef typename _Dp::param_type _Pp;
30730b57cec5SDimitry Andric    difference_type __d = __last - __first;
30740b57cec5SDimitry Andric    if (__d > 1)
30750b57cec5SDimitry Andric    {
30760b57cec5SDimitry Andric        _Dp __uid;
30770b57cec5SDimitry Andric        __rs_default __g = __rs_get();
30780b57cec5SDimitry Andric        for (--__last, (void) --__d; __first < __last; ++__first, (void) --__d)
30790b57cec5SDimitry Andric        {
30800b57cec5SDimitry Andric            difference_type __i = __uid(__g, _Pp(0, __d));
30810b57cec5SDimitry Andric            if (__i != difference_type(0))
30820b57cec5SDimitry Andric                swap(*__first, *(__first + __i));
30830b57cec5SDimitry Andric        }
30840b57cec5SDimitry Andric    }
30850b57cec5SDimitry Andric}
30860b57cec5SDimitry Andric
30870b57cec5SDimitry Andrictemplate <class _RandomAccessIterator, class _RandomNumberGenerator>
30880b57cec5SDimitry Andric_LIBCPP_DEPRECATED_IN_CXX14 void
30890b57cec5SDimitry Andricrandom_shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last,
30900b57cec5SDimitry Andric#ifndef _LIBCPP_CXX03_LANG
30910b57cec5SDimitry Andric               _RandomNumberGenerator&& __rand)
30920b57cec5SDimitry Andric#else
30930b57cec5SDimitry Andric               _RandomNumberGenerator& __rand)
30940b57cec5SDimitry Andric#endif
30950b57cec5SDimitry Andric{
30960b57cec5SDimitry Andric    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
30970b57cec5SDimitry Andric    difference_type __d = __last - __first;
30980b57cec5SDimitry Andric    if (__d > 1)
30990b57cec5SDimitry Andric    {
31000b57cec5SDimitry Andric        for (--__last; __first < __last; ++__first, (void) --__d)
31010b57cec5SDimitry Andric        {
31020b57cec5SDimitry Andric            difference_type __i = __rand(__d);
31030b57cec5SDimitry Andric            if (__i != difference_type(0))
31040b57cec5SDimitry Andric              swap(*__first, *(__first + __i));
31050b57cec5SDimitry Andric        }
31060b57cec5SDimitry Andric    }
31070b57cec5SDimitry Andric}
31080b57cec5SDimitry Andric#endif
31090b57cec5SDimitry Andric
31100b57cec5SDimitry Andrictemplate <class _PopulationIterator, class _SampleIterator, class _Distance,
31110b57cec5SDimitry Andric          class _UniformRandomNumberGenerator>
31120b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY
31130b57cec5SDimitry Andric_SampleIterator __sample(_PopulationIterator __first,
31140b57cec5SDimitry Andric                         _PopulationIterator __last, _SampleIterator __output_iter,
31150b57cec5SDimitry Andric                         _Distance __n,
31160b57cec5SDimitry Andric                         _UniformRandomNumberGenerator & __g,
31170b57cec5SDimitry Andric                         input_iterator_tag) {
31180b57cec5SDimitry Andric
31190b57cec5SDimitry Andric  _Distance __k = 0;
31200b57cec5SDimitry Andric  for (; __first != __last && __k < __n; ++__first, (void) ++__k)
31210b57cec5SDimitry Andric    __output_iter[__k] = *__first;
31220b57cec5SDimitry Andric  _Distance __sz = __k;
31230b57cec5SDimitry Andric  for (; __first != __last; ++__first, (void) ++__k) {
31240b57cec5SDimitry Andric    _Distance __r = _VSTD::uniform_int_distribution<_Distance>(0, __k)(__g);
31250b57cec5SDimitry Andric    if (__r < __sz)
31260b57cec5SDimitry Andric      __output_iter[__r] = *__first;
31270b57cec5SDimitry Andric  }
31280b57cec5SDimitry Andric  return __output_iter + _VSTD::min(__n, __k);
31290b57cec5SDimitry Andric}
31300b57cec5SDimitry Andric
31310b57cec5SDimitry Andrictemplate <class _PopulationIterator, class _SampleIterator, class _Distance,
31320b57cec5SDimitry Andric          class _UniformRandomNumberGenerator>
31330b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY
31340b57cec5SDimitry Andric_SampleIterator __sample(_PopulationIterator __first,
31350b57cec5SDimitry Andric                         _PopulationIterator __last, _SampleIterator __output_iter,
31360b57cec5SDimitry Andric                         _Distance __n,
31370b57cec5SDimitry Andric                         _UniformRandomNumberGenerator& __g,
31380b57cec5SDimitry Andric                         forward_iterator_tag) {
31390b57cec5SDimitry Andric  _Distance __unsampled_sz = _VSTD::distance(__first, __last);
31400b57cec5SDimitry Andric  for (__n = _VSTD::min(__n, __unsampled_sz); __n != 0; ++__first) {
31410b57cec5SDimitry Andric    _Distance __r =
31420b57cec5SDimitry Andric        _VSTD::uniform_int_distribution<_Distance>(0, --__unsampled_sz)(__g);
31430b57cec5SDimitry Andric    if (__r < __n) {
31440b57cec5SDimitry Andric      *__output_iter++ = *__first;
31450b57cec5SDimitry Andric      --__n;
31460b57cec5SDimitry Andric    }
31470b57cec5SDimitry Andric  }
31480b57cec5SDimitry Andric  return __output_iter;
31490b57cec5SDimitry Andric}
31500b57cec5SDimitry Andric
31510b57cec5SDimitry Andrictemplate <class _PopulationIterator, class _SampleIterator, class _Distance,
31520b57cec5SDimitry Andric          class _UniformRandomNumberGenerator>
31530b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY
31540b57cec5SDimitry Andric_SampleIterator __sample(_PopulationIterator __first,
31550b57cec5SDimitry Andric                         _PopulationIterator __last, _SampleIterator __output_iter,
31560b57cec5SDimitry Andric                         _Distance __n, _UniformRandomNumberGenerator& __g) {
31570b57cec5SDimitry Andric  typedef typename iterator_traits<_PopulationIterator>::iterator_category
31580b57cec5SDimitry Andric        _PopCategory;
31590b57cec5SDimitry Andric  typedef typename iterator_traits<_PopulationIterator>::difference_type
31600b57cec5SDimitry Andric        _Difference;
31610b57cec5SDimitry Andric  static_assert(__is_forward_iterator<_PopulationIterator>::value ||
31620b57cec5SDimitry Andric                __is_random_access_iterator<_SampleIterator>::value,
31630b57cec5SDimitry Andric                "SampleIterator must meet the requirements of RandomAccessIterator");
31640b57cec5SDimitry Andric  typedef typename common_type<_Distance, _Difference>::type _CommonType;
31650b57cec5SDimitry Andric  _LIBCPP_ASSERT(__n >= 0, "N must be a positive number.");
31660b57cec5SDimitry Andric  return _VSTD::__sample(
31670b57cec5SDimitry Andric      __first, __last, __output_iter, _CommonType(__n),
31680b57cec5SDimitry Andric      __g, _PopCategory());
31690b57cec5SDimitry Andric}
31700b57cec5SDimitry Andric
31710b57cec5SDimitry Andric#if _LIBCPP_STD_VER > 14
31720b57cec5SDimitry Andrictemplate <class _PopulationIterator, class _SampleIterator, class _Distance,
31730b57cec5SDimitry Andric          class _UniformRandomNumberGenerator>
31740b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
31750b57cec5SDimitry Andric_SampleIterator sample(_PopulationIterator __first,
31760b57cec5SDimitry Andric                       _PopulationIterator __last, _SampleIterator __output_iter,
31770b57cec5SDimitry Andric                       _Distance __n, _UniformRandomNumberGenerator&& __g) {
31780b57cec5SDimitry Andric    return _VSTD::__sample(__first, __last, __output_iter, __n, __g);
31790b57cec5SDimitry Andric}
31800b57cec5SDimitry Andric#endif // _LIBCPP_STD_VER > 14
31810b57cec5SDimitry Andric
31820b57cec5SDimitry Andrictemplate<class _RandomAccessIterator, class _UniformRandomNumberGenerator>
31830b57cec5SDimitry Andric    void shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last,
31840b57cec5SDimitry Andric                 _UniformRandomNumberGenerator&& __g)
31850b57cec5SDimitry Andric{
31860b57cec5SDimitry Andric    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
31870b57cec5SDimitry Andric    typedef uniform_int_distribution<ptrdiff_t> _Dp;
31880b57cec5SDimitry Andric    typedef typename _Dp::param_type _Pp;
31890b57cec5SDimitry Andric    difference_type __d = __last - __first;
31900b57cec5SDimitry Andric    if (__d > 1)
31910b57cec5SDimitry Andric    {
31920b57cec5SDimitry Andric        _Dp __uid;
3193*e40139ffSDimitry Andric        for (--__last, (void) --__d; __first < __last; ++__first, (void) --__d)
31940b57cec5SDimitry Andric        {
31950b57cec5SDimitry Andric            difference_type __i = __uid(__g, _Pp(0, __d));
31960b57cec5SDimitry Andric            if (__i != difference_type(0))
31970b57cec5SDimitry Andric                swap(*__first, *(__first + __i));
31980b57cec5SDimitry Andric        }
31990b57cec5SDimitry Andric    }
32000b57cec5SDimitry Andric}
32010b57cec5SDimitry Andric
32020b57cec5SDimitry Andrictemplate <class _InputIterator, class _Predicate>
32030b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 bool
32040b57cec5SDimitry Andricis_partitioned(_InputIterator __first, _InputIterator __last, _Predicate __pred)
32050b57cec5SDimitry Andric{
32060b57cec5SDimitry Andric    for (; __first != __last; ++__first)
32070b57cec5SDimitry Andric        if (!__pred(*__first))
32080b57cec5SDimitry Andric            break;
32090b57cec5SDimitry Andric    if ( __first == __last )
32100b57cec5SDimitry Andric        return true;
32110b57cec5SDimitry Andric    ++__first;
32120b57cec5SDimitry Andric    for (; __first != __last; ++__first)
32130b57cec5SDimitry Andric        if (__pred(*__first))
32140b57cec5SDimitry Andric            return false;
32150b57cec5SDimitry Andric    return true;
32160b57cec5SDimitry Andric}
32170b57cec5SDimitry Andric
32180b57cec5SDimitry Andric// partition
32190b57cec5SDimitry Andric
32200b57cec5SDimitry Andrictemplate <class _Predicate, class _ForwardIterator>
32210b57cec5SDimitry Andric_ForwardIterator
32220b57cec5SDimitry Andric__partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred, forward_iterator_tag)
32230b57cec5SDimitry Andric{
32240b57cec5SDimitry Andric    while (true)
32250b57cec5SDimitry Andric    {
32260b57cec5SDimitry Andric        if (__first == __last)
32270b57cec5SDimitry Andric            return __first;
32280b57cec5SDimitry Andric        if (!__pred(*__first))
32290b57cec5SDimitry Andric            break;
32300b57cec5SDimitry Andric        ++__first;
32310b57cec5SDimitry Andric    }
32320b57cec5SDimitry Andric    for (_ForwardIterator __p = __first; ++__p != __last;)
32330b57cec5SDimitry Andric    {
32340b57cec5SDimitry Andric        if (__pred(*__p))
32350b57cec5SDimitry Andric        {
32360b57cec5SDimitry Andric            swap(*__first, *__p);
32370b57cec5SDimitry Andric            ++__first;
32380b57cec5SDimitry Andric        }
32390b57cec5SDimitry Andric    }
32400b57cec5SDimitry Andric    return __first;
32410b57cec5SDimitry Andric}
32420b57cec5SDimitry Andric
32430b57cec5SDimitry Andrictemplate <class _Predicate, class _BidirectionalIterator>
32440b57cec5SDimitry Andric_BidirectionalIterator
32450b57cec5SDimitry Andric__partition(_BidirectionalIterator __first, _BidirectionalIterator __last, _Predicate __pred,
32460b57cec5SDimitry Andric            bidirectional_iterator_tag)
32470b57cec5SDimitry Andric{
32480b57cec5SDimitry Andric    while (true)
32490b57cec5SDimitry Andric    {
32500b57cec5SDimitry Andric        while (true)
32510b57cec5SDimitry Andric        {
32520b57cec5SDimitry Andric            if (__first == __last)
32530b57cec5SDimitry Andric                return __first;
32540b57cec5SDimitry Andric            if (!__pred(*__first))
32550b57cec5SDimitry Andric                break;
32560b57cec5SDimitry Andric            ++__first;
32570b57cec5SDimitry Andric        }
32580b57cec5SDimitry Andric        do
32590b57cec5SDimitry Andric        {
32600b57cec5SDimitry Andric            if (__first == --__last)
32610b57cec5SDimitry Andric                return __first;
32620b57cec5SDimitry Andric        } while (!__pred(*__last));
32630b57cec5SDimitry Andric        swap(*__first, *__last);
32640b57cec5SDimitry Andric        ++__first;
32650b57cec5SDimitry Andric    }
32660b57cec5SDimitry Andric}
32670b57cec5SDimitry Andric
32680b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Predicate>
32690b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
32700b57cec5SDimitry Andric_ForwardIterator
32710b57cec5SDimitry Andricpartition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred)
32720b57cec5SDimitry Andric{
32730b57cec5SDimitry Andric    return _VSTD::__partition<typename add_lvalue_reference<_Predicate>::type>
32740b57cec5SDimitry Andric                            (__first, __last, __pred, typename iterator_traits<_ForwardIterator>::iterator_category());
32750b57cec5SDimitry Andric}
32760b57cec5SDimitry Andric
32770b57cec5SDimitry Andric// partition_copy
32780b57cec5SDimitry Andric
32790b57cec5SDimitry Andrictemplate <class _InputIterator, class _OutputIterator1,
32800b57cec5SDimitry Andric          class _OutputIterator2, class _Predicate>
32810b57cec5SDimitry Andric_LIBCPP_CONSTEXPR_AFTER_CXX17 pair<_OutputIterator1, _OutputIterator2>
32820b57cec5SDimitry Andricpartition_copy(_InputIterator __first, _InputIterator __last,
32830b57cec5SDimitry Andric               _OutputIterator1 __out_true, _OutputIterator2 __out_false,
32840b57cec5SDimitry Andric               _Predicate __pred)
32850b57cec5SDimitry Andric{
32860b57cec5SDimitry Andric    for (; __first != __last; ++__first)
32870b57cec5SDimitry Andric    {
32880b57cec5SDimitry Andric        if (__pred(*__first))
32890b57cec5SDimitry Andric        {
32900b57cec5SDimitry Andric            *__out_true = *__first;
32910b57cec5SDimitry Andric            ++__out_true;
32920b57cec5SDimitry Andric        }
32930b57cec5SDimitry Andric        else
32940b57cec5SDimitry Andric        {
32950b57cec5SDimitry Andric            *__out_false = *__first;
32960b57cec5SDimitry Andric            ++__out_false;
32970b57cec5SDimitry Andric        }
32980b57cec5SDimitry Andric    }
32990b57cec5SDimitry Andric    return pair<_OutputIterator1, _OutputIterator2>(__out_true, __out_false);
33000b57cec5SDimitry Andric}
33010b57cec5SDimitry Andric
33020b57cec5SDimitry Andric// partition_point
33030b57cec5SDimitry Andric
33040b57cec5SDimitry Andrictemplate<class _ForwardIterator, class _Predicate>
33050b57cec5SDimitry Andric_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
33060b57cec5SDimitry Andricpartition_point(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred)
33070b57cec5SDimitry Andric{
33080b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
33090b57cec5SDimitry Andric    difference_type __len = _VSTD::distance(__first, __last);
33100b57cec5SDimitry Andric    while (__len != 0)
33110b57cec5SDimitry Andric    {
33120b57cec5SDimitry Andric        difference_type __l2 = _VSTD::__half_positive(__len);
33130b57cec5SDimitry Andric        _ForwardIterator __m = __first;
33140b57cec5SDimitry Andric        _VSTD::advance(__m, __l2);
33150b57cec5SDimitry Andric        if (__pred(*__m))
33160b57cec5SDimitry Andric        {
33170b57cec5SDimitry Andric            __first = ++__m;
33180b57cec5SDimitry Andric            __len -= __l2 + 1;
33190b57cec5SDimitry Andric        }
33200b57cec5SDimitry Andric        else
33210b57cec5SDimitry Andric            __len = __l2;
33220b57cec5SDimitry Andric    }
33230b57cec5SDimitry Andric    return __first;
33240b57cec5SDimitry Andric}
33250b57cec5SDimitry Andric
33260b57cec5SDimitry Andric// stable_partition
33270b57cec5SDimitry Andric
33280b57cec5SDimitry Andrictemplate <class _Predicate, class _ForwardIterator, class _Distance, class _Pair>
33290b57cec5SDimitry Andric_ForwardIterator
33300b57cec5SDimitry Andric__stable_partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred,
33310b57cec5SDimitry Andric                   _Distance __len, _Pair __p, forward_iterator_tag __fit)
33320b57cec5SDimitry Andric{
33330b57cec5SDimitry Andric    // *__first is known to be false
33340b57cec5SDimitry Andric    // __len >= 1
33350b57cec5SDimitry Andric    if (__len == 1)
33360b57cec5SDimitry Andric        return __first;
33370b57cec5SDimitry Andric    if (__len == 2)
33380b57cec5SDimitry Andric    {
33390b57cec5SDimitry Andric        _ForwardIterator __m = __first;
33400b57cec5SDimitry Andric        if (__pred(*++__m))
33410b57cec5SDimitry Andric        {
33420b57cec5SDimitry Andric            swap(*__first, *__m);
33430b57cec5SDimitry Andric            return __m;
33440b57cec5SDimitry Andric        }
33450b57cec5SDimitry Andric        return __first;
33460b57cec5SDimitry Andric    }
33470b57cec5SDimitry Andric    if (__len <= __p.second)
33480b57cec5SDimitry Andric    {   // The buffer is big enough to use
33490b57cec5SDimitry Andric        typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
33500b57cec5SDimitry Andric        __destruct_n __d(0);
33510b57cec5SDimitry Andric        unique_ptr<value_type, __destruct_n&> __h(__p.first, __d);
33520b57cec5SDimitry Andric        // Move the falses into the temporary buffer, and the trues to the front of the line
33530b57cec5SDimitry Andric        // Update __first to always point to the end of the trues
33540b57cec5SDimitry Andric        value_type* __t = __p.first;
33550b57cec5SDimitry Andric        ::new(__t) value_type(_VSTD::move(*__first));
33560b57cec5SDimitry Andric        __d.__incr((value_type*)0);
33570b57cec5SDimitry Andric        ++__t;
33580b57cec5SDimitry Andric        _ForwardIterator __i = __first;
33590b57cec5SDimitry Andric        while (++__i != __last)
33600b57cec5SDimitry Andric        {
33610b57cec5SDimitry Andric            if (__pred(*__i))
33620b57cec5SDimitry Andric            {
33630b57cec5SDimitry Andric                *__first = _VSTD::move(*__i);
33640b57cec5SDimitry Andric                ++__first;
33650b57cec5SDimitry Andric            }
33660b57cec5SDimitry Andric            else
33670b57cec5SDimitry Andric            {
33680b57cec5SDimitry Andric                ::new(__t) value_type(_VSTD::move(*__i));
33690b57cec5SDimitry Andric                __d.__incr((value_type*)0);
33700b57cec5SDimitry Andric                ++__t;
33710b57cec5SDimitry Andric            }
33720b57cec5SDimitry Andric        }
33730b57cec5SDimitry Andric        // All trues now at start of range, all falses in buffer
33740b57cec5SDimitry Andric        // Move falses back into range, but don't mess up __first which points to first false
33750b57cec5SDimitry Andric        __i = __first;
3376*e40139ffSDimitry Andric        for (value_type* __t2 = __p.first; __t2 < __t; ++__t2, (void) ++__i)
33770b57cec5SDimitry Andric            *__i = _VSTD::move(*__t2);
33780b57cec5SDimitry Andric        // __h destructs moved-from values out of the temp buffer, but doesn't deallocate buffer
33790b57cec5SDimitry Andric        return __first;
33800b57cec5SDimitry Andric    }
33810b57cec5SDimitry Andric    // Else not enough buffer, do in place
33820b57cec5SDimitry Andric    // __len >= 3
33830b57cec5SDimitry Andric    _ForwardIterator __m = __first;
33840b57cec5SDimitry Andric    _Distance __len2 = __len / 2;  // __len2 >= 2
33850b57cec5SDimitry Andric    _VSTD::advance(__m, __len2);
33860b57cec5SDimitry Andric    // recurse on [__first, __m), *__first know to be false
33870b57cec5SDimitry Andric    // F?????????????????
33880b57cec5SDimitry Andric    // f       m         l
33890b57cec5SDimitry Andric    typedef typename add_lvalue_reference<_Predicate>::type _PredRef;
33900b57cec5SDimitry Andric    _ForwardIterator __first_false = __stable_partition<_PredRef>(__first, __m, __pred, __len2, __p, __fit);
33910b57cec5SDimitry Andric    // TTTFFFFF??????????
33920b57cec5SDimitry Andric    // f  ff   m         l
33930b57cec5SDimitry Andric    // recurse on [__m, __last], except increase __m until *(__m) is false, *__last know to be true
33940b57cec5SDimitry Andric    _ForwardIterator __m1 = __m;
33950b57cec5SDimitry Andric    _ForwardIterator __second_false = __last;
33960b57cec5SDimitry Andric    _Distance __len_half = __len - __len2;
33970b57cec5SDimitry Andric    while (__pred(*__m1))
33980b57cec5SDimitry Andric    {
33990b57cec5SDimitry Andric        if (++__m1 == __last)
34000b57cec5SDimitry Andric            goto __second_half_done;
34010b57cec5SDimitry Andric        --__len_half;
34020b57cec5SDimitry Andric    }
34030b57cec5SDimitry Andric    // TTTFFFFFTTTF??????
34040b57cec5SDimitry Andric    // f  ff   m  m1     l
34050b57cec5SDimitry Andric    __second_false = __stable_partition<_PredRef>(__m1, __last, __pred, __len_half, __p, __fit);
34060b57cec5SDimitry Andric__second_half_done:
34070b57cec5SDimitry Andric    // TTTFFFFFTTTTTFFFFF
34080b57cec5SDimitry Andric    // f  ff   m    sf   l
34090b57cec5SDimitry Andric    return _VSTD::rotate(__first_false, __m, __second_false);
34100b57cec5SDimitry Andric    // TTTTTTTTFFFFFFFFFF
34110b57cec5SDimitry Andric    //         |
34120b57cec5SDimitry Andric}
34130b57cec5SDimitry Andric
34140b57cec5SDimitry Andricstruct __return_temporary_buffer
34150b57cec5SDimitry Andric{
34160b57cec5SDimitry Andric    template <class _Tp>
34170b57cec5SDimitry Andric    _LIBCPP_INLINE_VISIBILITY void operator()(_Tp* __p) const {_VSTD::return_temporary_buffer(__p);}
34180b57cec5SDimitry Andric};
34190b57cec5SDimitry Andric
34200b57cec5SDimitry Andrictemplate <class _Predicate, class _ForwardIterator>
34210b57cec5SDimitry Andric_ForwardIterator
34220b57cec5SDimitry Andric__stable_partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred,
34230b57cec5SDimitry Andric                   forward_iterator_tag)
34240b57cec5SDimitry Andric{
34250b57cec5SDimitry Andric    const unsigned __alloc_limit = 3;  // might want to make this a function of trivial assignment
34260b57cec5SDimitry Andric    // Either prove all true and return __first or point to first false
34270b57cec5SDimitry Andric    while (true)
34280b57cec5SDimitry Andric    {
34290b57cec5SDimitry Andric        if (__first == __last)
34300b57cec5SDimitry Andric            return __first;
34310b57cec5SDimitry Andric        if (!__pred(*__first))
34320b57cec5SDimitry Andric            break;
34330b57cec5SDimitry Andric        ++__first;
34340b57cec5SDimitry Andric    }
34350b57cec5SDimitry Andric    // We now have a reduced range [__first, __last)
34360b57cec5SDimitry Andric    // *__first is known to be false
34370b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
34380b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
34390b57cec5SDimitry Andric    difference_type __len = _VSTD::distance(__first, __last);
34400b57cec5SDimitry Andric    pair<value_type*, ptrdiff_t> __p(0, 0);
34410b57cec5SDimitry Andric    unique_ptr<value_type, __return_temporary_buffer> __h;
34420b57cec5SDimitry Andric    if (__len >= __alloc_limit)
34430b57cec5SDimitry Andric    {
34440b57cec5SDimitry Andric        __p = _VSTD::get_temporary_buffer<value_type>(__len);
34450b57cec5SDimitry Andric        __h.reset(__p.first);
34460b57cec5SDimitry Andric    }
34470b57cec5SDimitry Andric    return __stable_partition<typename add_lvalue_reference<_Predicate>::type>
34480b57cec5SDimitry Andric                             (__first, __last, __pred, __len, __p, forward_iterator_tag());
34490b57cec5SDimitry Andric}
34500b57cec5SDimitry Andric
34510b57cec5SDimitry Andrictemplate <class _Predicate, class _BidirectionalIterator, class _Distance, class _Pair>
34520b57cec5SDimitry Andric_BidirectionalIterator
34530b57cec5SDimitry Andric__stable_partition(_BidirectionalIterator __first, _BidirectionalIterator __last, _Predicate __pred,
34540b57cec5SDimitry Andric                   _Distance __len, _Pair __p, bidirectional_iterator_tag __bit)
34550b57cec5SDimitry Andric{
34560b57cec5SDimitry Andric    // *__first is known to be false
34570b57cec5SDimitry Andric    // *__last is known to be true
34580b57cec5SDimitry Andric    // __len >= 2
34590b57cec5SDimitry Andric    if (__len == 2)
34600b57cec5SDimitry Andric    {
34610b57cec5SDimitry Andric        swap(*__first, *__last);
34620b57cec5SDimitry Andric        return __last;
34630b57cec5SDimitry Andric    }
34640b57cec5SDimitry Andric    if (__len == 3)
34650b57cec5SDimitry Andric    {
34660b57cec5SDimitry Andric        _BidirectionalIterator __m = __first;
34670b57cec5SDimitry Andric        if (__pred(*++__m))
34680b57cec5SDimitry Andric        {
34690b57cec5SDimitry Andric            swap(*__first, *__m);
34700b57cec5SDimitry Andric            swap(*__m, *__last);
34710b57cec5SDimitry Andric            return __last;
34720b57cec5SDimitry Andric        }
34730b57cec5SDimitry Andric        swap(*__m, *__last);
34740b57cec5SDimitry Andric        swap(*__first, *__m);
34750b57cec5SDimitry Andric        return __m;
34760b57cec5SDimitry Andric    }
34770b57cec5SDimitry Andric    if (__len <= __p.second)
34780b57cec5SDimitry Andric    {   // The buffer is big enough to use
34790b57cec5SDimitry Andric        typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
34800b57cec5SDimitry Andric        __destruct_n __d(0);
34810b57cec5SDimitry Andric        unique_ptr<value_type, __destruct_n&> __h(__p.first, __d);
34820b57cec5SDimitry Andric        // Move the falses into the temporary buffer, and the trues to the front of the line
34830b57cec5SDimitry Andric        // Update __first to always point to the end of the trues
34840b57cec5SDimitry Andric        value_type* __t = __p.first;
34850b57cec5SDimitry Andric        ::new(__t) value_type(_VSTD::move(*__first));
34860b57cec5SDimitry Andric        __d.__incr((value_type*)0);
34870b57cec5SDimitry Andric        ++__t;
34880b57cec5SDimitry Andric        _BidirectionalIterator __i = __first;
34890b57cec5SDimitry Andric        while (++__i != __last)
34900b57cec5SDimitry Andric        {
34910b57cec5SDimitry Andric            if (__pred(*__i))
34920b57cec5SDimitry Andric            {
34930b57cec5SDimitry Andric                *__first = _VSTD::move(*__i);
34940b57cec5SDimitry Andric                ++__first;
34950b57cec5SDimitry Andric            }
34960b57cec5SDimitry Andric            else
34970b57cec5SDimitry Andric            {
34980b57cec5SDimitry Andric                ::new(__t) value_type(_VSTD::move(*__i));
34990b57cec5SDimitry Andric                __d.__incr((value_type*)0);
35000b57cec5SDimitry Andric                ++__t;
35010b57cec5SDimitry Andric            }
35020b57cec5SDimitry Andric        }
35030b57cec5SDimitry Andric        // move *__last, known to be true
35040b57cec5SDimitry Andric        *__first = _VSTD::move(*__i);
35050b57cec5SDimitry Andric        __i = ++__first;
35060b57cec5SDimitry Andric        // All trues now at start of range, all falses in buffer
35070b57cec5SDimitry Andric        // Move falses back into range, but don't mess up __first which points to first false
3508*e40139ffSDimitry Andric        for (value_type* __t2 = __p.first; __t2 < __t; ++__t2, (void) ++__i)
35090b57cec5SDimitry Andric            *__i = _VSTD::move(*__t2);
35100b57cec5SDimitry Andric        // __h destructs moved-from values out of the temp buffer, but doesn't deallocate buffer
35110b57cec5SDimitry Andric        return __first;
35120b57cec5SDimitry Andric    }
35130b57cec5SDimitry Andric    // Else not enough buffer, do in place
35140b57cec5SDimitry Andric    // __len >= 4
35150b57cec5SDimitry Andric    _BidirectionalIterator __m = __first;
35160b57cec5SDimitry Andric    _Distance __len2 = __len / 2;  // __len2 >= 2
35170b57cec5SDimitry Andric    _VSTD::advance(__m, __len2);
35180b57cec5SDimitry Andric    // recurse on [__first, __m-1], except reduce __m-1 until *(__m-1) is true, *__first know to be false
35190b57cec5SDimitry Andric    // F????????????????T
35200b57cec5SDimitry Andric    // f       m        l
35210b57cec5SDimitry Andric    _BidirectionalIterator __m1 = __m;
35220b57cec5SDimitry Andric    _BidirectionalIterator __first_false = __first;
35230b57cec5SDimitry Andric    _Distance __len_half = __len2;
35240b57cec5SDimitry Andric    while (!__pred(*--__m1))
35250b57cec5SDimitry Andric    {
35260b57cec5SDimitry Andric        if (__m1 == __first)
35270b57cec5SDimitry Andric            goto __first_half_done;
35280b57cec5SDimitry Andric        --__len_half;
35290b57cec5SDimitry Andric    }
35300b57cec5SDimitry Andric    // F???TFFF?????????T
35310b57cec5SDimitry Andric    // f   m1  m        l
35320b57cec5SDimitry Andric    typedef typename add_lvalue_reference<_Predicate>::type _PredRef;
35330b57cec5SDimitry Andric    __first_false = __stable_partition<_PredRef>(__first, __m1, __pred, __len_half, __p, __bit);
35340b57cec5SDimitry Andric__first_half_done:
35350b57cec5SDimitry Andric    // TTTFFFFF?????????T
35360b57cec5SDimitry Andric    // f  ff   m        l
35370b57cec5SDimitry Andric    // recurse on [__m, __last], except increase __m until *(__m) is false, *__last know to be true
35380b57cec5SDimitry Andric    __m1 = __m;
35390b57cec5SDimitry Andric    _BidirectionalIterator __second_false = __last;
35400b57cec5SDimitry Andric    ++__second_false;
35410b57cec5SDimitry Andric    __len_half = __len - __len2;
35420b57cec5SDimitry Andric    while (__pred(*__m1))
35430b57cec5SDimitry Andric    {
35440b57cec5SDimitry Andric        if (++__m1 == __last)
35450b57cec5SDimitry Andric            goto __second_half_done;
35460b57cec5SDimitry Andric        --__len_half;
35470b57cec5SDimitry Andric    }
35480b57cec5SDimitry Andric    // TTTFFFFFTTTF?????T
35490b57cec5SDimitry Andric    // f  ff   m  m1    l
35500b57cec5SDimitry Andric    __second_false = __stable_partition<_PredRef>(__m1, __last, __pred, __len_half, __p, __bit);
35510b57cec5SDimitry Andric__second_half_done:
35520b57cec5SDimitry Andric    // TTTFFFFFTTTTTFFFFF
35530b57cec5SDimitry Andric    // f  ff   m    sf  l
35540b57cec5SDimitry Andric    return _VSTD::rotate(__first_false, __m, __second_false);
35550b57cec5SDimitry Andric    // TTTTTTTTFFFFFFFFFF
35560b57cec5SDimitry Andric    //         |
35570b57cec5SDimitry Andric}
35580b57cec5SDimitry Andric
35590b57cec5SDimitry Andrictemplate <class _Predicate, class _BidirectionalIterator>
35600b57cec5SDimitry Andric_BidirectionalIterator
35610b57cec5SDimitry Andric__stable_partition(_BidirectionalIterator __first, _BidirectionalIterator __last, _Predicate __pred,
35620b57cec5SDimitry Andric                   bidirectional_iterator_tag)
35630b57cec5SDimitry Andric{
35640b57cec5SDimitry Andric    typedef typename iterator_traits<_BidirectionalIterator>::difference_type difference_type;
35650b57cec5SDimitry Andric    typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
35660b57cec5SDimitry Andric    const difference_type __alloc_limit = 4;  // might want to make this a function of trivial assignment
35670b57cec5SDimitry Andric    // Either prove all true and return __first or point to first false
35680b57cec5SDimitry Andric    while (true)
35690b57cec5SDimitry Andric    {
35700b57cec5SDimitry Andric        if (__first == __last)
35710b57cec5SDimitry Andric            return __first;
35720b57cec5SDimitry Andric        if (!__pred(*__first))
35730b57cec5SDimitry Andric            break;
35740b57cec5SDimitry Andric        ++__first;
35750b57cec5SDimitry Andric    }
35760b57cec5SDimitry Andric    // __first points to first false, everything prior to __first is already set.
35770b57cec5SDimitry Andric    // Either prove [__first, __last) is all false and return __first, or point __last to last true
35780b57cec5SDimitry Andric    do
35790b57cec5SDimitry Andric    {
35800b57cec5SDimitry Andric        if (__first == --__last)
35810b57cec5SDimitry Andric            return __first;
35820b57cec5SDimitry Andric    } while (!__pred(*__last));
35830b57cec5SDimitry Andric    // We now have a reduced range [__first, __last]
35840b57cec5SDimitry Andric    // *__first is known to be false
35850b57cec5SDimitry Andric    // *__last is known to be true
35860b57cec5SDimitry Andric    // __len >= 2
35870b57cec5SDimitry Andric    difference_type __len = _VSTD::distance(__first, __last) + 1;
35880b57cec5SDimitry Andric    pair<value_type*, ptrdiff_t> __p(0, 0);
35890b57cec5SDimitry Andric    unique_ptr<value_type, __return_temporary_buffer> __h;
35900b57cec5SDimitry Andric    if (__len >= __alloc_limit)
35910b57cec5SDimitry Andric    {
35920b57cec5SDimitry Andric        __p = _VSTD::get_temporary_buffer<value_type>(__len);
35930b57cec5SDimitry Andric        __h.reset(__p.first);
35940b57cec5SDimitry Andric    }
35950b57cec5SDimitry Andric    return __stable_partition<typename add_lvalue_reference<_Predicate>::type>
35960b57cec5SDimitry Andric                             (__first, __last, __pred, __len, __p, bidirectional_iterator_tag());
35970b57cec5SDimitry Andric}
35980b57cec5SDimitry Andric
35990b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Predicate>
36000b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
36010b57cec5SDimitry Andric_ForwardIterator
36020b57cec5SDimitry Andricstable_partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred)
36030b57cec5SDimitry Andric{
36040b57cec5SDimitry Andric    return __stable_partition<typename add_lvalue_reference<_Predicate>::type>
36050b57cec5SDimitry Andric                             (__first, __last, __pred, typename iterator_traits<_ForwardIterator>::iterator_category());
36060b57cec5SDimitry Andric}
36070b57cec5SDimitry Andric
36080b57cec5SDimitry Andric// is_sorted_until
36090b57cec5SDimitry Andric
36100b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Compare>
36110b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
36120b57cec5SDimitry Andricis_sorted_until(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
36130b57cec5SDimitry Andric{
36140b57cec5SDimitry Andric    if (__first != __last)
36150b57cec5SDimitry Andric    {
36160b57cec5SDimitry Andric        _ForwardIterator __i = __first;
36170b57cec5SDimitry Andric        while (++__i != __last)
36180b57cec5SDimitry Andric        {
36190b57cec5SDimitry Andric            if (__comp(*__i, *__first))
36200b57cec5SDimitry Andric                return __i;
36210b57cec5SDimitry Andric            __first = __i;
36220b57cec5SDimitry Andric        }
36230b57cec5SDimitry Andric    }
36240b57cec5SDimitry Andric    return __last;
36250b57cec5SDimitry Andric}
36260b57cec5SDimitry Andric
36270b57cec5SDimitry Andrictemplate<class _ForwardIterator>
36280b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
36290b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
36300b57cec5SDimitry Andric_ForwardIterator
36310b57cec5SDimitry Andricis_sorted_until(_ForwardIterator __first, _ForwardIterator __last)
36320b57cec5SDimitry Andric{
36330b57cec5SDimitry Andric    return _VSTD::is_sorted_until(__first, __last, __less<typename iterator_traits<_ForwardIterator>::value_type>());
36340b57cec5SDimitry Andric}
36350b57cec5SDimitry Andric
36360b57cec5SDimitry Andric// is_sorted
36370b57cec5SDimitry Andric
36380b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Compare>
36390b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
36400b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
36410b57cec5SDimitry Andricbool
36420b57cec5SDimitry Andricis_sorted(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
36430b57cec5SDimitry Andric{
36440b57cec5SDimitry Andric    return _VSTD::is_sorted_until(__first, __last, __comp) == __last;
36450b57cec5SDimitry Andric}
36460b57cec5SDimitry Andric
36470b57cec5SDimitry Andrictemplate<class _ForwardIterator>
36480b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
36490b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
36500b57cec5SDimitry Andricbool
36510b57cec5SDimitry Andricis_sorted(_ForwardIterator __first, _ForwardIterator __last)
36520b57cec5SDimitry Andric{
36530b57cec5SDimitry Andric    return _VSTD::is_sorted(__first, __last, __less<typename iterator_traits<_ForwardIterator>::value_type>());
36540b57cec5SDimitry Andric}
36550b57cec5SDimitry Andric
36560b57cec5SDimitry Andric// sort
36570b57cec5SDimitry Andric
36580b57cec5SDimitry Andric// stable, 2-3 compares, 0-2 swaps
36590b57cec5SDimitry Andric
36600b57cec5SDimitry Andrictemplate <class _Compare, class _ForwardIterator>
36610b57cec5SDimitry Andricunsigned
36620b57cec5SDimitry Andric__sort3(_ForwardIterator __x, _ForwardIterator __y, _ForwardIterator __z, _Compare __c)
36630b57cec5SDimitry Andric{
36640b57cec5SDimitry Andric    unsigned __r = 0;
36650b57cec5SDimitry Andric    if (!__c(*__y, *__x))          // if x <= y
36660b57cec5SDimitry Andric    {
36670b57cec5SDimitry Andric        if (!__c(*__z, *__y))      // if y <= z
36680b57cec5SDimitry Andric            return __r;            // x <= y && y <= z
36690b57cec5SDimitry Andric                                   // x <= y && y > z
36700b57cec5SDimitry Andric        swap(*__y, *__z);          // x <= z && y < z
36710b57cec5SDimitry Andric        __r = 1;
36720b57cec5SDimitry Andric        if (__c(*__y, *__x))       // if x > y
36730b57cec5SDimitry Andric        {
36740b57cec5SDimitry Andric            swap(*__x, *__y);      // x < y && y <= z
36750b57cec5SDimitry Andric            __r = 2;
36760b57cec5SDimitry Andric        }
36770b57cec5SDimitry Andric        return __r;                // x <= y && y < z
36780b57cec5SDimitry Andric    }
36790b57cec5SDimitry Andric    if (__c(*__z, *__y))           // x > y, if y > z
36800b57cec5SDimitry Andric    {
36810b57cec5SDimitry Andric        swap(*__x, *__z);          // x < y && y < z
36820b57cec5SDimitry Andric        __r = 1;
36830b57cec5SDimitry Andric        return __r;
36840b57cec5SDimitry Andric    }
36850b57cec5SDimitry Andric    swap(*__x, *__y);              // x > y && y <= z
36860b57cec5SDimitry Andric    __r = 1;                       // x < y && x <= z
36870b57cec5SDimitry Andric    if (__c(*__z, *__y))           // if y > z
36880b57cec5SDimitry Andric    {
36890b57cec5SDimitry Andric        swap(*__y, *__z);          // x <= y && y < z
36900b57cec5SDimitry Andric        __r = 2;
36910b57cec5SDimitry Andric    }
36920b57cec5SDimitry Andric    return __r;
36930b57cec5SDimitry Andric}                                  // x <= y && y <= z
36940b57cec5SDimitry Andric
36950b57cec5SDimitry Andric// stable, 3-6 compares, 0-5 swaps
36960b57cec5SDimitry Andric
36970b57cec5SDimitry Andrictemplate <class _Compare, class _ForwardIterator>
36980b57cec5SDimitry Andricunsigned
36990b57cec5SDimitry Andric__sort4(_ForwardIterator __x1, _ForwardIterator __x2, _ForwardIterator __x3,
37000b57cec5SDimitry Andric            _ForwardIterator __x4, _Compare __c)
37010b57cec5SDimitry Andric{
37020b57cec5SDimitry Andric    unsigned __r = __sort3<_Compare>(__x1, __x2, __x3, __c);
37030b57cec5SDimitry Andric    if (__c(*__x4, *__x3))
37040b57cec5SDimitry Andric    {
37050b57cec5SDimitry Andric        swap(*__x3, *__x4);
37060b57cec5SDimitry Andric        ++__r;
37070b57cec5SDimitry Andric        if (__c(*__x3, *__x2))
37080b57cec5SDimitry Andric        {
37090b57cec5SDimitry Andric            swap(*__x2, *__x3);
37100b57cec5SDimitry Andric            ++__r;
37110b57cec5SDimitry Andric            if (__c(*__x2, *__x1))
37120b57cec5SDimitry Andric            {
37130b57cec5SDimitry Andric                swap(*__x1, *__x2);
37140b57cec5SDimitry Andric                ++__r;
37150b57cec5SDimitry Andric            }
37160b57cec5SDimitry Andric        }
37170b57cec5SDimitry Andric    }
37180b57cec5SDimitry Andric    return __r;
37190b57cec5SDimitry Andric}
37200b57cec5SDimitry Andric
37210b57cec5SDimitry Andric// stable, 4-10 compares, 0-9 swaps
37220b57cec5SDimitry Andric
37230b57cec5SDimitry Andrictemplate <class _Compare, class _ForwardIterator>
37240b57cec5SDimitry Andric_LIBCPP_HIDDEN
37250b57cec5SDimitry Andricunsigned
37260b57cec5SDimitry Andric__sort5(_ForwardIterator __x1, _ForwardIterator __x2, _ForwardIterator __x3,
37270b57cec5SDimitry Andric            _ForwardIterator __x4, _ForwardIterator __x5, _Compare __c)
37280b57cec5SDimitry Andric{
37290b57cec5SDimitry Andric    unsigned __r = __sort4<_Compare>(__x1, __x2, __x3, __x4, __c);
37300b57cec5SDimitry Andric    if (__c(*__x5, *__x4))
37310b57cec5SDimitry Andric    {
37320b57cec5SDimitry Andric        swap(*__x4, *__x5);
37330b57cec5SDimitry Andric        ++__r;
37340b57cec5SDimitry Andric        if (__c(*__x4, *__x3))
37350b57cec5SDimitry Andric        {
37360b57cec5SDimitry Andric            swap(*__x3, *__x4);
37370b57cec5SDimitry Andric            ++__r;
37380b57cec5SDimitry Andric            if (__c(*__x3, *__x2))
37390b57cec5SDimitry Andric            {
37400b57cec5SDimitry Andric                swap(*__x2, *__x3);
37410b57cec5SDimitry Andric                ++__r;
37420b57cec5SDimitry Andric                if (__c(*__x2, *__x1))
37430b57cec5SDimitry Andric                {
37440b57cec5SDimitry Andric                    swap(*__x1, *__x2);
37450b57cec5SDimitry Andric                    ++__r;
37460b57cec5SDimitry Andric                }
37470b57cec5SDimitry Andric            }
37480b57cec5SDimitry Andric        }
37490b57cec5SDimitry Andric    }
37500b57cec5SDimitry Andric    return __r;
37510b57cec5SDimitry Andric}
37520b57cec5SDimitry Andric
37530b57cec5SDimitry Andric// Assumes size > 0
37540b57cec5SDimitry Andrictemplate <class _Compare, class _BirdirectionalIterator>
37550b57cec5SDimitry Andricvoid
37560b57cec5SDimitry Andric__selection_sort(_BirdirectionalIterator __first, _BirdirectionalIterator __last, _Compare __comp)
37570b57cec5SDimitry Andric{
37580b57cec5SDimitry Andric    _BirdirectionalIterator __lm1 = __last;
37590b57cec5SDimitry Andric    for (--__lm1; __first != __lm1; ++__first)
37600b57cec5SDimitry Andric    {
37610b57cec5SDimitry Andric        _BirdirectionalIterator __i = _VSTD::min_element<_BirdirectionalIterator,
37620b57cec5SDimitry Andric                                                        typename add_lvalue_reference<_Compare>::type>
37630b57cec5SDimitry Andric                                                       (__first, __last, __comp);
37640b57cec5SDimitry Andric        if (__i != __first)
37650b57cec5SDimitry Andric            swap(*__first, *__i);
37660b57cec5SDimitry Andric    }
37670b57cec5SDimitry Andric}
37680b57cec5SDimitry Andric
37690b57cec5SDimitry Andrictemplate <class _Compare, class _BirdirectionalIterator>
37700b57cec5SDimitry Andricvoid
37710b57cec5SDimitry Andric__insertion_sort(_BirdirectionalIterator __first, _BirdirectionalIterator __last, _Compare __comp)
37720b57cec5SDimitry Andric{
37730b57cec5SDimitry Andric    typedef typename iterator_traits<_BirdirectionalIterator>::value_type value_type;
37740b57cec5SDimitry Andric    if (__first != __last)
37750b57cec5SDimitry Andric    {
37760b57cec5SDimitry Andric        _BirdirectionalIterator __i = __first;
37770b57cec5SDimitry Andric        for (++__i; __i != __last; ++__i)
37780b57cec5SDimitry Andric        {
37790b57cec5SDimitry Andric            _BirdirectionalIterator __j = __i;
37800b57cec5SDimitry Andric            value_type __t(_VSTD::move(*__j));
37810b57cec5SDimitry Andric            for (_BirdirectionalIterator __k = __i; __k != __first && __comp(__t,  *--__k); --__j)
37820b57cec5SDimitry Andric                *__j = _VSTD::move(*__k);
37830b57cec5SDimitry Andric            *__j = _VSTD::move(__t);
37840b57cec5SDimitry Andric        }
37850b57cec5SDimitry Andric    }
37860b57cec5SDimitry Andric}
37870b57cec5SDimitry Andric
37880b57cec5SDimitry Andrictemplate <class _Compare, class _RandomAccessIterator>
37890b57cec5SDimitry Andricvoid
37900b57cec5SDimitry Andric__insertion_sort_3(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
37910b57cec5SDimitry Andric{
37920b57cec5SDimitry Andric    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
37930b57cec5SDimitry Andric    _RandomAccessIterator __j = __first+2;
37940b57cec5SDimitry Andric    __sort3<_Compare>(__first, __first+1, __j, __comp);
37950b57cec5SDimitry Andric    for (_RandomAccessIterator __i = __j+1; __i != __last; ++__i)
37960b57cec5SDimitry Andric    {
37970b57cec5SDimitry Andric        if (__comp(*__i, *__j))
37980b57cec5SDimitry Andric        {
37990b57cec5SDimitry Andric            value_type __t(_VSTD::move(*__i));
38000b57cec5SDimitry Andric            _RandomAccessIterator __k = __j;
38010b57cec5SDimitry Andric            __j = __i;
38020b57cec5SDimitry Andric            do
38030b57cec5SDimitry Andric            {
38040b57cec5SDimitry Andric                *__j = _VSTD::move(*__k);
38050b57cec5SDimitry Andric                __j = __k;
38060b57cec5SDimitry Andric            } while (__j != __first && __comp(__t, *--__k));
38070b57cec5SDimitry Andric            *__j = _VSTD::move(__t);
38080b57cec5SDimitry Andric        }
38090b57cec5SDimitry Andric        __j = __i;
38100b57cec5SDimitry Andric    }
38110b57cec5SDimitry Andric}
38120b57cec5SDimitry Andric
38130b57cec5SDimitry Andrictemplate <class _Compare, class _RandomAccessIterator>
38140b57cec5SDimitry Andricbool
38150b57cec5SDimitry Andric__insertion_sort_incomplete(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
38160b57cec5SDimitry Andric{
38170b57cec5SDimitry Andric    switch (__last - __first)
38180b57cec5SDimitry Andric    {
38190b57cec5SDimitry Andric    case 0:
38200b57cec5SDimitry Andric    case 1:
38210b57cec5SDimitry Andric        return true;
38220b57cec5SDimitry Andric    case 2:
38230b57cec5SDimitry Andric        if (__comp(*--__last, *__first))
38240b57cec5SDimitry Andric            swap(*__first, *__last);
38250b57cec5SDimitry Andric        return true;
38260b57cec5SDimitry Andric    case 3:
38270b57cec5SDimitry Andric        _VSTD::__sort3<_Compare>(__first, __first+1, --__last, __comp);
38280b57cec5SDimitry Andric        return true;
38290b57cec5SDimitry Andric    case 4:
38300b57cec5SDimitry Andric        _VSTD::__sort4<_Compare>(__first, __first+1, __first+2, --__last, __comp);
38310b57cec5SDimitry Andric        return true;
38320b57cec5SDimitry Andric    case 5:
38330b57cec5SDimitry Andric        _VSTD::__sort5<_Compare>(__first, __first+1, __first+2, __first+3, --__last, __comp);
38340b57cec5SDimitry Andric        return true;
38350b57cec5SDimitry Andric    }
38360b57cec5SDimitry Andric    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
38370b57cec5SDimitry Andric    _RandomAccessIterator __j = __first+2;
38380b57cec5SDimitry Andric    __sort3<_Compare>(__first, __first+1, __j, __comp);
38390b57cec5SDimitry Andric    const unsigned __limit = 8;
38400b57cec5SDimitry Andric    unsigned __count = 0;
38410b57cec5SDimitry Andric    for (_RandomAccessIterator __i = __j+1; __i != __last; ++__i)
38420b57cec5SDimitry Andric    {
38430b57cec5SDimitry Andric        if (__comp(*__i, *__j))
38440b57cec5SDimitry Andric        {
38450b57cec5SDimitry Andric            value_type __t(_VSTD::move(*__i));
38460b57cec5SDimitry Andric            _RandomAccessIterator __k = __j;
38470b57cec5SDimitry Andric            __j = __i;
38480b57cec5SDimitry Andric            do
38490b57cec5SDimitry Andric            {
38500b57cec5SDimitry Andric                *__j = _VSTD::move(*__k);
38510b57cec5SDimitry Andric                __j = __k;
38520b57cec5SDimitry Andric            } while (__j != __first && __comp(__t, *--__k));
38530b57cec5SDimitry Andric            *__j = _VSTD::move(__t);
38540b57cec5SDimitry Andric            if (++__count == __limit)
38550b57cec5SDimitry Andric                return ++__i == __last;
38560b57cec5SDimitry Andric        }
38570b57cec5SDimitry Andric        __j = __i;
38580b57cec5SDimitry Andric    }
38590b57cec5SDimitry Andric    return true;
38600b57cec5SDimitry Andric}
38610b57cec5SDimitry Andric
38620b57cec5SDimitry Andrictemplate <class _Compare, class _BirdirectionalIterator>
38630b57cec5SDimitry Andricvoid
38640b57cec5SDimitry Andric__insertion_sort_move(_BirdirectionalIterator __first1, _BirdirectionalIterator __last1,
38650b57cec5SDimitry Andric                      typename iterator_traits<_BirdirectionalIterator>::value_type* __first2, _Compare __comp)
38660b57cec5SDimitry Andric{
38670b57cec5SDimitry Andric    typedef typename iterator_traits<_BirdirectionalIterator>::value_type value_type;
38680b57cec5SDimitry Andric    if (__first1 != __last1)
38690b57cec5SDimitry Andric    {
38700b57cec5SDimitry Andric        __destruct_n __d(0);
38710b57cec5SDimitry Andric        unique_ptr<value_type, __destruct_n&> __h(__first2, __d);
38720b57cec5SDimitry Andric        value_type* __last2 = __first2;
38730b57cec5SDimitry Andric        ::new(__last2) value_type(_VSTD::move(*__first1));
38740b57cec5SDimitry Andric        __d.__incr((value_type*)0);
38750b57cec5SDimitry Andric        for (++__last2; ++__first1 != __last1; ++__last2)
38760b57cec5SDimitry Andric        {
38770b57cec5SDimitry Andric            value_type* __j2 = __last2;
38780b57cec5SDimitry Andric            value_type* __i2 = __j2;
38790b57cec5SDimitry Andric            if (__comp(*__first1, *--__i2))
38800b57cec5SDimitry Andric            {
38810b57cec5SDimitry Andric                ::new(__j2) value_type(_VSTD::move(*__i2));
38820b57cec5SDimitry Andric                __d.__incr((value_type*)0);
38830b57cec5SDimitry Andric                for (--__j2; __i2 != __first2 && __comp(*__first1,  *--__i2); --__j2)
38840b57cec5SDimitry Andric                    *__j2 = _VSTD::move(*__i2);
38850b57cec5SDimitry Andric                *__j2 = _VSTD::move(*__first1);
38860b57cec5SDimitry Andric            }
38870b57cec5SDimitry Andric            else
38880b57cec5SDimitry Andric            {
38890b57cec5SDimitry Andric                ::new(__j2) value_type(_VSTD::move(*__first1));
38900b57cec5SDimitry Andric                __d.__incr((value_type*)0);
38910b57cec5SDimitry Andric            }
38920b57cec5SDimitry Andric        }
38930b57cec5SDimitry Andric        __h.release();
38940b57cec5SDimitry Andric    }
38950b57cec5SDimitry Andric}
38960b57cec5SDimitry Andric
38970b57cec5SDimitry Andrictemplate <class _Compare, class _RandomAccessIterator>
38980b57cec5SDimitry Andricvoid
38990b57cec5SDimitry Andric__sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
39000b57cec5SDimitry Andric{
39010b57cec5SDimitry Andric    // _Compare is known to be a reference type
39020b57cec5SDimitry Andric    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
39030b57cec5SDimitry Andric    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
39040b57cec5SDimitry Andric    const difference_type __limit = is_trivially_copy_constructible<value_type>::value &&
39050b57cec5SDimitry Andric                                    is_trivially_copy_assignable<value_type>::value ? 30 : 6;
39060b57cec5SDimitry Andric    while (true)
39070b57cec5SDimitry Andric    {
39080b57cec5SDimitry Andric    __restart:
39090b57cec5SDimitry Andric        difference_type __len = __last - __first;
39100b57cec5SDimitry Andric        switch (__len)
39110b57cec5SDimitry Andric        {
39120b57cec5SDimitry Andric        case 0:
39130b57cec5SDimitry Andric        case 1:
39140b57cec5SDimitry Andric            return;
39150b57cec5SDimitry Andric        case 2:
39160b57cec5SDimitry Andric            if (__comp(*--__last, *__first))
39170b57cec5SDimitry Andric                swap(*__first, *__last);
39180b57cec5SDimitry Andric            return;
39190b57cec5SDimitry Andric        case 3:
39200b57cec5SDimitry Andric            _VSTD::__sort3<_Compare>(__first, __first+1, --__last, __comp);
39210b57cec5SDimitry Andric            return;
39220b57cec5SDimitry Andric        case 4:
39230b57cec5SDimitry Andric            _VSTD::__sort4<_Compare>(__first, __first+1, __first+2, --__last, __comp);
39240b57cec5SDimitry Andric            return;
39250b57cec5SDimitry Andric        case 5:
39260b57cec5SDimitry Andric            _VSTD::__sort5<_Compare>(__first, __first+1, __first+2, __first+3, --__last, __comp);
39270b57cec5SDimitry Andric            return;
39280b57cec5SDimitry Andric        }
39290b57cec5SDimitry Andric        if (__len <= __limit)
39300b57cec5SDimitry Andric        {
39310b57cec5SDimitry Andric            _VSTD::__insertion_sort_3<_Compare>(__first, __last, __comp);
39320b57cec5SDimitry Andric            return;
39330b57cec5SDimitry Andric        }
39340b57cec5SDimitry Andric        // __len > 5
39350b57cec5SDimitry Andric        _RandomAccessIterator __m = __first;
39360b57cec5SDimitry Andric        _RandomAccessIterator __lm1 = __last;
39370b57cec5SDimitry Andric        --__lm1;
39380b57cec5SDimitry Andric        unsigned __n_swaps;
39390b57cec5SDimitry Andric        {
39400b57cec5SDimitry Andric        difference_type __delta;
39410b57cec5SDimitry Andric        if (__len >= 1000)
39420b57cec5SDimitry Andric        {
39430b57cec5SDimitry Andric            __delta = __len/2;
39440b57cec5SDimitry Andric            __m += __delta;
39450b57cec5SDimitry Andric            __delta /= 2;
39460b57cec5SDimitry Andric            __n_swaps = _VSTD::__sort5<_Compare>(__first, __first + __delta, __m, __m+__delta, __lm1, __comp);
39470b57cec5SDimitry Andric        }
39480b57cec5SDimitry Andric        else
39490b57cec5SDimitry Andric        {
39500b57cec5SDimitry Andric            __delta = __len/2;
39510b57cec5SDimitry Andric            __m += __delta;
39520b57cec5SDimitry Andric            __n_swaps = _VSTD::__sort3<_Compare>(__first, __m, __lm1, __comp);
39530b57cec5SDimitry Andric        }
39540b57cec5SDimitry Andric        }
39550b57cec5SDimitry Andric        // *__m is median
39560b57cec5SDimitry Andric        // partition [__first, __m) < *__m and *__m <= [__m, __last)
39570b57cec5SDimitry Andric        // (this inhibits tossing elements equivalent to __m around unnecessarily)
39580b57cec5SDimitry Andric        _RandomAccessIterator __i = __first;
39590b57cec5SDimitry Andric        _RandomAccessIterator __j = __lm1;
39600b57cec5SDimitry Andric        // j points beyond range to be tested, *__m is known to be <= *__lm1
39610b57cec5SDimitry Andric        // The search going up is known to be guarded but the search coming down isn't.
39620b57cec5SDimitry Andric        // Prime the downward search with a guard.
39630b57cec5SDimitry Andric        if (!__comp(*__i, *__m))  // if *__first == *__m
39640b57cec5SDimitry Andric        {
39650b57cec5SDimitry Andric            // *__first == *__m, *__first doesn't go in first part
39660b57cec5SDimitry Andric            // manually guard downward moving __j against __i
39670b57cec5SDimitry Andric            while (true)
39680b57cec5SDimitry Andric            {
39690b57cec5SDimitry Andric                if (__i == --__j)
39700b57cec5SDimitry Andric                {
39710b57cec5SDimitry Andric                    // *__first == *__m, *__m <= all other elements
39720b57cec5SDimitry Andric                    // Parition instead into [__first, __i) == *__first and *__first < [__i, __last)
39730b57cec5SDimitry Andric                    ++__i;  // __first + 1
39740b57cec5SDimitry Andric                    __j = __last;
39750b57cec5SDimitry Andric                    if (!__comp(*__first, *--__j))  // we need a guard if *__first == *(__last-1)
39760b57cec5SDimitry Andric                    {
39770b57cec5SDimitry Andric                        while (true)
39780b57cec5SDimitry Andric                        {
39790b57cec5SDimitry Andric                            if (__i == __j)
39800b57cec5SDimitry Andric                                return;  // [__first, __last) all equivalent elements
39810b57cec5SDimitry Andric                            if (__comp(*__first, *__i))
39820b57cec5SDimitry Andric                            {
39830b57cec5SDimitry Andric                                swap(*__i, *__j);
39840b57cec5SDimitry Andric                                ++__n_swaps;
39850b57cec5SDimitry Andric                                ++__i;
39860b57cec5SDimitry Andric                                break;
39870b57cec5SDimitry Andric                            }
39880b57cec5SDimitry Andric                            ++__i;
39890b57cec5SDimitry Andric                        }
39900b57cec5SDimitry Andric                    }
39910b57cec5SDimitry Andric                    // [__first, __i) == *__first and *__first < [__j, __last) and __j == __last - 1
39920b57cec5SDimitry Andric                    if (__i == __j)
39930b57cec5SDimitry Andric                        return;
39940b57cec5SDimitry Andric                    while (true)
39950b57cec5SDimitry Andric                    {
39960b57cec5SDimitry Andric                        while (!__comp(*__first, *__i))
39970b57cec5SDimitry Andric                            ++__i;
39980b57cec5SDimitry Andric                        while (__comp(*__first, *--__j))
39990b57cec5SDimitry Andric                            ;
40000b57cec5SDimitry Andric                        if (__i >= __j)
40010b57cec5SDimitry Andric                            break;
40020b57cec5SDimitry Andric                        swap(*__i, *__j);
40030b57cec5SDimitry Andric                        ++__n_swaps;
40040b57cec5SDimitry Andric                        ++__i;
40050b57cec5SDimitry Andric                    }
40060b57cec5SDimitry Andric                    // [__first, __i) == *__first and *__first < [__i, __last)
40070b57cec5SDimitry Andric                    // The first part is sorted, sort the secod part
40080b57cec5SDimitry Andric                    // _VSTD::__sort<_Compare>(__i, __last, __comp);
40090b57cec5SDimitry Andric                    __first = __i;
40100b57cec5SDimitry Andric                    goto __restart;
40110b57cec5SDimitry Andric                }
40120b57cec5SDimitry Andric                if (__comp(*__j, *__m))
40130b57cec5SDimitry Andric                {
40140b57cec5SDimitry Andric                    swap(*__i, *__j);
40150b57cec5SDimitry Andric                    ++__n_swaps;
40160b57cec5SDimitry Andric                    break;  // found guard for downward moving __j, now use unguarded partition
40170b57cec5SDimitry Andric                }
40180b57cec5SDimitry Andric            }
40190b57cec5SDimitry Andric        }
40200b57cec5SDimitry Andric        // It is known that *__i < *__m
40210b57cec5SDimitry Andric        ++__i;
40220b57cec5SDimitry Andric        // j points beyond range to be tested, *__m is known to be <= *__lm1
40230b57cec5SDimitry Andric        // if not yet partitioned...
40240b57cec5SDimitry Andric        if (__i < __j)
40250b57cec5SDimitry Andric        {
40260b57cec5SDimitry Andric            // known that *(__i - 1) < *__m
40270b57cec5SDimitry Andric            // known that __i <= __m
40280b57cec5SDimitry Andric            while (true)
40290b57cec5SDimitry Andric            {
40300b57cec5SDimitry Andric                // __m still guards upward moving __i
40310b57cec5SDimitry Andric                while (__comp(*__i, *__m))
40320b57cec5SDimitry Andric                    ++__i;
40330b57cec5SDimitry Andric                // It is now known that a guard exists for downward moving __j
40340b57cec5SDimitry Andric                while (!__comp(*--__j, *__m))
40350b57cec5SDimitry Andric                    ;
40360b57cec5SDimitry Andric                if (__i > __j)
40370b57cec5SDimitry Andric                    break;
40380b57cec5SDimitry Andric                swap(*__i, *__j);
40390b57cec5SDimitry Andric                ++__n_swaps;
40400b57cec5SDimitry Andric                // It is known that __m != __j
40410b57cec5SDimitry Andric                // If __m just moved, follow it
40420b57cec5SDimitry Andric                if (__m == __i)
40430b57cec5SDimitry Andric                    __m = __j;
40440b57cec5SDimitry Andric                ++__i;
40450b57cec5SDimitry Andric            }
40460b57cec5SDimitry Andric        }
40470b57cec5SDimitry Andric        // [__first, __i) < *__m and *__m <= [__i, __last)
40480b57cec5SDimitry Andric        if (__i != __m && __comp(*__m, *__i))
40490b57cec5SDimitry Andric        {
40500b57cec5SDimitry Andric            swap(*__i, *__m);
40510b57cec5SDimitry Andric            ++__n_swaps;
40520b57cec5SDimitry Andric        }
40530b57cec5SDimitry Andric        // [__first, __i) < *__i and *__i <= [__i+1, __last)
40540b57cec5SDimitry Andric        // If we were given a perfect partition, see if insertion sort is quick...
40550b57cec5SDimitry Andric        if (__n_swaps == 0)
40560b57cec5SDimitry Andric        {
40570b57cec5SDimitry Andric            bool __fs = _VSTD::__insertion_sort_incomplete<_Compare>(__first, __i, __comp);
40580b57cec5SDimitry Andric            if (_VSTD::__insertion_sort_incomplete<_Compare>(__i+1, __last, __comp))
40590b57cec5SDimitry Andric            {
40600b57cec5SDimitry Andric                if (__fs)
40610b57cec5SDimitry Andric                    return;
40620b57cec5SDimitry Andric                __last = __i;
40630b57cec5SDimitry Andric                continue;
40640b57cec5SDimitry Andric            }
40650b57cec5SDimitry Andric            else
40660b57cec5SDimitry Andric            {
40670b57cec5SDimitry Andric                if (__fs)
40680b57cec5SDimitry Andric                {
40690b57cec5SDimitry Andric                    __first = ++__i;
40700b57cec5SDimitry Andric                    continue;
40710b57cec5SDimitry Andric                }
40720b57cec5SDimitry Andric            }
40730b57cec5SDimitry Andric        }
40740b57cec5SDimitry Andric        // sort smaller range with recursive call and larger with tail recursion elimination
40750b57cec5SDimitry Andric        if (__i - __first < __last - __i)
40760b57cec5SDimitry Andric        {
40770b57cec5SDimitry Andric            _VSTD::__sort<_Compare>(__first, __i, __comp);
40780b57cec5SDimitry Andric            // _VSTD::__sort<_Compare>(__i+1, __last, __comp);
40790b57cec5SDimitry Andric            __first = ++__i;
40800b57cec5SDimitry Andric        }
40810b57cec5SDimitry Andric        else
40820b57cec5SDimitry Andric        {
40830b57cec5SDimitry Andric            _VSTD::__sort<_Compare>(__i+1, __last, __comp);
40840b57cec5SDimitry Andric            // _VSTD::__sort<_Compare>(__first, __i, __comp);
40850b57cec5SDimitry Andric            __last = __i;
40860b57cec5SDimitry Andric        }
40870b57cec5SDimitry Andric    }
40880b57cec5SDimitry Andric}
40890b57cec5SDimitry Andric
40900b57cec5SDimitry Andric// This forwarder keeps the top call and the recursive calls using the same instantiation, forcing a reference _Compare
40910b57cec5SDimitry Andrictemplate <class _RandomAccessIterator, class _Compare>
40920b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
40930b57cec5SDimitry Andricvoid
40940b57cec5SDimitry Andricsort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
40950b57cec5SDimitry Andric{
40960b57cec5SDimitry Andric    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
40970b57cec5SDimitry Andric    _VSTD::__sort<_Comp_ref>(__first, __last, _Comp_ref(__comp));
40980b57cec5SDimitry Andric}
40990b57cec5SDimitry Andric
41000b57cec5SDimitry Andrictemplate <class _RandomAccessIterator>
41010b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
41020b57cec5SDimitry Andricvoid
41030b57cec5SDimitry Andricsort(_RandomAccessIterator __first, _RandomAccessIterator __last)
41040b57cec5SDimitry Andric{
41050b57cec5SDimitry Andric    _VSTD::sort(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
41060b57cec5SDimitry Andric}
41070b57cec5SDimitry Andric
41080b57cec5SDimitry Andrictemplate <class _Tp>
41090b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
41100b57cec5SDimitry Andricvoid
41110b57cec5SDimitry Andricsort(_Tp** __first, _Tp** __last)
41120b57cec5SDimitry Andric{
41130b57cec5SDimitry Andric    _VSTD::sort((size_t*)__first, (size_t*)__last, __less<size_t>());
41140b57cec5SDimitry Andric}
41150b57cec5SDimitry Andric
41160b57cec5SDimitry Andrictemplate <class _Tp>
41170b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
41180b57cec5SDimitry Andricvoid
41190b57cec5SDimitry Andricsort(__wrap_iter<_Tp*> __first, __wrap_iter<_Tp*> __last)
41200b57cec5SDimitry Andric{
41210b57cec5SDimitry Andric    _VSTD::sort(__first.base(), __last.base());
41220b57cec5SDimitry Andric}
41230b57cec5SDimitry Andric
41240b57cec5SDimitry Andrictemplate <class _Tp, class _Compare>
41250b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
41260b57cec5SDimitry Andricvoid
41270b57cec5SDimitry Andricsort(__wrap_iter<_Tp*> __first, __wrap_iter<_Tp*> __last, _Compare __comp)
41280b57cec5SDimitry Andric{
41290b57cec5SDimitry Andric    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
41300b57cec5SDimitry Andric    _VSTD::sort<_Tp*, _Comp_ref>(__first.base(), __last.base(), __comp);
41310b57cec5SDimitry Andric}
41320b57cec5SDimitry Andric
41330b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<char>&, char*>(char*, char*, __less<char>&))
41340b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<wchar_t>&, wchar_t*>(wchar_t*, wchar_t*, __less<wchar_t>&))
41350b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<signed char>&, signed char*>(signed char*, signed char*, __less<signed char>&))
41360b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned char>&, unsigned char*>(unsigned char*, unsigned char*, __less<unsigned char>&))
41370b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<short>&, short*>(short*, short*, __less<short>&))
41380b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned short>&, unsigned short*>(unsigned short*, unsigned short*, __less<unsigned short>&))
41390b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<int>&, int*>(int*, int*, __less<int>&))
41400b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned>&, unsigned*>(unsigned*, unsigned*, __less<unsigned>&))
41410b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<long>&, long*>(long*, long*, __less<long>&))
41420b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned long>&, unsigned long*>(unsigned long*, unsigned long*, __less<unsigned long>&))
41430b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<long long>&, long long*>(long long*, long long*, __less<long long>&))
41440b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned long long>&, unsigned long long*>(unsigned long long*, unsigned long long*, __less<unsigned long long>&))
41450b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<float>&, float*>(float*, float*, __less<float>&))
41460b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<double>&, double*>(double*, double*, __less<double>&))
41470b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<long double>&, long double*>(long double*, long double*, __less<long double>&))
41480b57cec5SDimitry Andric
41490b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<char>&, char*>(char*, char*, __less<char>&))
41500b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<wchar_t>&, wchar_t*>(wchar_t*, wchar_t*, __less<wchar_t>&))
41510b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<signed char>&, signed char*>(signed char*, signed char*, __less<signed char>&))
41520b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned char>&, unsigned char*>(unsigned char*, unsigned char*, __less<unsigned char>&))
41530b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<short>&, short*>(short*, short*, __less<short>&))
41540b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned short>&, unsigned short*>(unsigned short*, unsigned short*, __less<unsigned short>&))
41550b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<int>&, int*>(int*, int*, __less<int>&))
41560b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned>&, unsigned*>(unsigned*, unsigned*, __less<unsigned>&))
41570b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<long>&, long*>(long*, long*, __less<long>&))
41580b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned long>&, unsigned long*>(unsigned long*, unsigned long*, __less<unsigned long>&))
41590b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<long long>&, long long*>(long long*, long long*, __less<long long>&))
41600b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned long long>&, unsigned long long*>(unsigned long long*, unsigned long long*, __less<unsigned long long>&))
41610b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<float>&, float*>(float*, float*, __less<float>&))
41620b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<double>&, double*>(double*, double*, __less<double>&))
41630b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<long double>&, long double*>(long double*, long double*, __less<long double>&))
41640b57cec5SDimitry Andric
41650b57cec5SDimitry Andric_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS unsigned __sort5<__less<long double>&, long double*>(long double*, long double*, long double*, long double*, long double*, __less<long double>&))
41660b57cec5SDimitry Andric
41670b57cec5SDimitry Andric// lower_bound
41680b57cec5SDimitry Andric
41690b57cec5SDimitry Andrictemplate <class _Compare, class _ForwardIterator, class _Tp>
41700b57cec5SDimitry Andric_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
41710b57cec5SDimitry Andric__lower_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
41720b57cec5SDimitry Andric{
41730b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
41740b57cec5SDimitry Andric    difference_type __len = _VSTD::distance(__first, __last);
41750b57cec5SDimitry Andric    while (__len != 0)
41760b57cec5SDimitry Andric    {
41770b57cec5SDimitry Andric        difference_type __l2 = _VSTD::__half_positive(__len);
41780b57cec5SDimitry Andric        _ForwardIterator __m = __first;
41790b57cec5SDimitry Andric        _VSTD::advance(__m, __l2);
41800b57cec5SDimitry Andric        if (__comp(*__m, __value_))
41810b57cec5SDimitry Andric        {
41820b57cec5SDimitry Andric            __first = ++__m;
41830b57cec5SDimitry Andric            __len -= __l2 + 1;
41840b57cec5SDimitry Andric        }
41850b57cec5SDimitry Andric        else
41860b57cec5SDimitry Andric            __len = __l2;
41870b57cec5SDimitry Andric    }
41880b57cec5SDimitry Andric    return __first;
41890b57cec5SDimitry Andric}
41900b57cec5SDimitry Andric
41910b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Tp, class _Compare>
41920b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
41930b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
41940b57cec5SDimitry Andric_ForwardIterator
41950b57cec5SDimitry Andriclower_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
41960b57cec5SDimitry Andric{
41970b57cec5SDimitry Andric    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
41980b57cec5SDimitry Andric    return __lower_bound<_Comp_ref>(__first, __last, __value_, __comp);
41990b57cec5SDimitry Andric}
42000b57cec5SDimitry Andric
42010b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Tp>
42020b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
42030b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
42040b57cec5SDimitry Andric_ForwardIterator
42050b57cec5SDimitry Andriclower_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
42060b57cec5SDimitry Andric{
42070b57cec5SDimitry Andric    return _VSTD::lower_bound(__first, __last, __value_,
42080b57cec5SDimitry Andric                             __less<typename iterator_traits<_ForwardIterator>::value_type, _Tp>());
42090b57cec5SDimitry Andric}
42100b57cec5SDimitry Andric
42110b57cec5SDimitry Andric// upper_bound
42120b57cec5SDimitry Andric
42130b57cec5SDimitry Andrictemplate <class _Compare, class _ForwardIterator, class _Tp>
42140b57cec5SDimitry Andric_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
42150b57cec5SDimitry Andric__upper_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
42160b57cec5SDimitry Andric{
42170b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
42180b57cec5SDimitry Andric    difference_type __len = _VSTD::distance(__first, __last);
42190b57cec5SDimitry Andric    while (__len != 0)
42200b57cec5SDimitry Andric    {
42210b57cec5SDimitry Andric        difference_type __l2 = _VSTD::__half_positive(__len);
42220b57cec5SDimitry Andric        _ForwardIterator __m = __first;
42230b57cec5SDimitry Andric        _VSTD::advance(__m, __l2);
42240b57cec5SDimitry Andric        if (__comp(__value_, *__m))
42250b57cec5SDimitry Andric            __len = __l2;
42260b57cec5SDimitry Andric        else
42270b57cec5SDimitry Andric        {
42280b57cec5SDimitry Andric            __first = ++__m;
42290b57cec5SDimitry Andric            __len -= __l2 + 1;
42300b57cec5SDimitry Andric        }
42310b57cec5SDimitry Andric    }
42320b57cec5SDimitry Andric    return __first;
42330b57cec5SDimitry Andric}
42340b57cec5SDimitry Andric
42350b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Tp, class _Compare>
42360b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
42370b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
42380b57cec5SDimitry Andric_ForwardIterator
42390b57cec5SDimitry Andricupper_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
42400b57cec5SDimitry Andric{
42410b57cec5SDimitry Andric    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
42420b57cec5SDimitry Andric    return __upper_bound<_Comp_ref>(__first, __last, __value_, __comp);
42430b57cec5SDimitry Andric}
42440b57cec5SDimitry Andric
42450b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Tp>
42460b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
42470b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
42480b57cec5SDimitry Andric_ForwardIterator
42490b57cec5SDimitry Andricupper_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
42500b57cec5SDimitry Andric{
42510b57cec5SDimitry Andric    return _VSTD::upper_bound(__first, __last, __value_,
42520b57cec5SDimitry Andric                             __less<_Tp, typename iterator_traits<_ForwardIterator>::value_type>());
42530b57cec5SDimitry Andric}
42540b57cec5SDimitry Andric
42550b57cec5SDimitry Andric// equal_range
42560b57cec5SDimitry Andric
42570b57cec5SDimitry Andrictemplate <class _Compare, class _ForwardIterator, class _Tp>
42580b57cec5SDimitry Andric_LIBCPP_CONSTEXPR_AFTER_CXX17 pair<_ForwardIterator, _ForwardIterator>
42590b57cec5SDimitry Andric__equal_range(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
42600b57cec5SDimitry Andric{
42610b57cec5SDimitry Andric    typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
42620b57cec5SDimitry Andric    difference_type __len = _VSTD::distance(__first, __last);
42630b57cec5SDimitry Andric    while (__len != 0)
42640b57cec5SDimitry Andric    {
42650b57cec5SDimitry Andric        difference_type __l2 = _VSTD::__half_positive(__len);
42660b57cec5SDimitry Andric        _ForwardIterator __m = __first;
42670b57cec5SDimitry Andric        _VSTD::advance(__m, __l2);
42680b57cec5SDimitry Andric        if (__comp(*__m, __value_))
42690b57cec5SDimitry Andric        {
42700b57cec5SDimitry Andric            __first = ++__m;
42710b57cec5SDimitry Andric            __len -= __l2 + 1;
42720b57cec5SDimitry Andric        }
42730b57cec5SDimitry Andric        else if (__comp(__value_, *__m))
42740b57cec5SDimitry Andric        {
42750b57cec5SDimitry Andric            __last = __m;
42760b57cec5SDimitry Andric            __len = __l2;
42770b57cec5SDimitry Andric        }
42780b57cec5SDimitry Andric        else
42790b57cec5SDimitry Andric        {
42800b57cec5SDimitry Andric            _ForwardIterator __mp1 = __m;
42810b57cec5SDimitry Andric            return pair<_ForwardIterator, _ForwardIterator>
42820b57cec5SDimitry Andric                   (
42830b57cec5SDimitry Andric                      __lower_bound<_Compare>(__first, __m, __value_, __comp),
42840b57cec5SDimitry Andric                      __upper_bound<_Compare>(++__mp1, __last, __value_, __comp)
42850b57cec5SDimitry Andric                   );
42860b57cec5SDimitry Andric        }
42870b57cec5SDimitry Andric    }
42880b57cec5SDimitry Andric    return pair<_ForwardIterator, _ForwardIterator>(__first, __first);
42890b57cec5SDimitry Andric}
42900b57cec5SDimitry Andric
42910b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Tp, class _Compare>
42920b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
42930b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
42940b57cec5SDimitry Andricpair<_ForwardIterator, _ForwardIterator>
42950b57cec5SDimitry Andricequal_range(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
42960b57cec5SDimitry Andric{
42970b57cec5SDimitry Andric    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
42980b57cec5SDimitry Andric    return __equal_range<_Comp_ref>(__first, __last, __value_, __comp);
42990b57cec5SDimitry Andric}
43000b57cec5SDimitry Andric
43010b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Tp>
43020b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
43030b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
43040b57cec5SDimitry Andricpair<_ForwardIterator, _ForwardIterator>
43050b57cec5SDimitry Andricequal_range(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
43060b57cec5SDimitry Andric{
43070b57cec5SDimitry Andric    return _VSTD::equal_range(__first, __last, __value_,
43080b57cec5SDimitry Andric                             __less<typename iterator_traits<_ForwardIterator>::value_type, _Tp>());
43090b57cec5SDimitry Andric}
43100b57cec5SDimitry Andric
43110b57cec5SDimitry Andric// binary_search
43120b57cec5SDimitry Andric
43130b57cec5SDimitry Andrictemplate <class _Compare, class _ForwardIterator, class _Tp>
43140b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
43150b57cec5SDimitry Andricbool
43160b57cec5SDimitry Andric__binary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
43170b57cec5SDimitry Andric{
43180b57cec5SDimitry Andric    __first = __lower_bound<_Compare>(__first, __last, __value_, __comp);
43190b57cec5SDimitry Andric    return __first != __last && !__comp(__value_, *__first);
43200b57cec5SDimitry Andric}
43210b57cec5SDimitry Andric
43220b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Tp, class _Compare>
43230b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
43240b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
43250b57cec5SDimitry Andricbool
43260b57cec5SDimitry Andricbinary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
43270b57cec5SDimitry Andric{
43280b57cec5SDimitry Andric    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
43290b57cec5SDimitry Andric    return __binary_search<_Comp_ref>(__first, __last, __value_, __comp);
43300b57cec5SDimitry Andric}
43310b57cec5SDimitry Andric
43320b57cec5SDimitry Andrictemplate <class _ForwardIterator, class _Tp>
43330b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
43340b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
43350b57cec5SDimitry Andricbool
43360b57cec5SDimitry Andricbinary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
43370b57cec5SDimitry Andric{
43380b57cec5SDimitry Andric    return _VSTD::binary_search(__first, __last, __value_,
43390b57cec5SDimitry Andric                             __less<typename iterator_traits<_ForwardIterator>::value_type, _Tp>());
43400b57cec5SDimitry Andric}
43410b57cec5SDimitry Andric
43420b57cec5SDimitry Andric// merge
43430b57cec5SDimitry Andric
43440b57cec5SDimitry Andrictemplate <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
43450b57cec5SDimitry Andric_OutputIterator
43460b57cec5SDimitry Andric__merge(_InputIterator1 __first1, _InputIterator1 __last1,
43470b57cec5SDimitry Andric        _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
43480b57cec5SDimitry Andric{
43490b57cec5SDimitry Andric    for (; __first1 != __last1; ++__result)
43500b57cec5SDimitry Andric    {
43510b57cec5SDimitry Andric        if (__first2 == __last2)
43520b57cec5SDimitry Andric            return _VSTD::copy(__first1, __last1, __result);
43530b57cec5SDimitry Andric        if (__comp(*__first2, *__first1))
43540b57cec5SDimitry Andric        {
43550b57cec5SDimitry Andric            *__result = *__first2;
43560b57cec5SDimitry Andric            ++__first2;
43570b57cec5SDimitry Andric        }
43580b57cec5SDimitry Andric        else
43590b57cec5SDimitry Andric        {
43600b57cec5SDimitry Andric            *__result = *__first1;
43610b57cec5SDimitry Andric            ++__first1;
43620b57cec5SDimitry Andric        }
43630b57cec5SDimitry Andric    }
43640b57cec5SDimitry Andric    return _VSTD::copy(__first2, __last2, __result);
43650b57cec5SDimitry Andric}
43660b57cec5SDimitry Andric
43670b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
43680b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
43690b57cec5SDimitry Andric_OutputIterator
43700b57cec5SDimitry Andricmerge(_InputIterator1 __first1, _InputIterator1 __last1,
43710b57cec5SDimitry Andric      _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
43720b57cec5SDimitry Andric{
43730b57cec5SDimitry Andric    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
43740b57cec5SDimitry Andric    return _VSTD::__merge<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
43750b57cec5SDimitry Andric}
43760b57cec5SDimitry Andric
43770b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator>
43780b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
43790b57cec5SDimitry Andric_OutputIterator
43800b57cec5SDimitry Andricmerge(_InputIterator1 __first1, _InputIterator1 __last1,
43810b57cec5SDimitry Andric      _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
43820b57cec5SDimitry Andric{
43830b57cec5SDimitry Andric    typedef typename iterator_traits<_InputIterator1>::value_type __v1;
43840b57cec5SDimitry Andric    typedef typename iterator_traits<_InputIterator2>::value_type __v2;
4385*e40139ffSDimitry Andric    return _VSTD::merge(__first1, __last1, __first2, __last2, __result, __less<__v1, __v2>());
43860b57cec5SDimitry Andric}
43870b57cec5SDimitry Andric
43880b57cec5SDimitry Andric// inplace_merge
43890b57cec5SDimitry Andric
43900b57cec5SDimitry Andrictemplate <class _Compare, class _InputIterator1, class _InputIterator2,
43910b57cec5SDimitry Andric          class _OutputIterator>
43920b57cec5SDimitry Andricvoid __half_inplace_merge(_InputIterator1 __first1, _InputIterator1 __last1,
43930b57cec5SDimitry Andric                          _InputIterator2 __first2, _InputIterator2 __last2,
43940b57cec5SDimitry Andric                          _OutputIterator __result, _Compare __comp)
43950b57cec5SDimitry Andric{
43960b57cec5SDimitry Andric    for (; __first1 != __last1; ++__result)
43970b57cec5SDimitry Andric    {
43980b57cec5SDimitry Andric        if (__first2 == __last2)
43990b57cec5SDimitry Andric        {
44000b57cec5SDimitry Andric            _VSTD::move(__first1, __last1, __result);
44010b57cec5SDimitry Andric            return;
44020b57cec5SDimitry Andric        }
44030b57cec5SDimitry Andric
44040b57cec5SDimitry Andric        if (__comp(*__first2, *__first1))
44050b57cec5SDimitry Andric        {
44060b57cec5SDimitry Andric            *__result = _VSTD::move(*__first2);
44070b57cec5SDimitry Andric            ++__first2;
44080b57cec5SDimitry Andric        }
44090b57cec5SDimitry Andric        else
44100b57cec5SDimitry Andric        {
44110b57cec5SDimitry Andric            *__result = _VSTD::move(*__first1);
44120b57cec5SDimitry Andric            ++__first1;
44130b57cec5SDimitry Andric        }
44140b57cec5SDimitry Andric    }
44150b57cec5SDimitry Andric    // __first2 through __last2 are already in the right spot.
44160b57cec5SDimitry Andric}
44170b57cec5SDimitry Andric
44180b57cec5SDimitry Andrictemplate <class _Compare, class _BidirectionalIterator>
44190b57cec5SDimitry Andricvoid
44200b57cec5SDimitry Andric__buffered_inplace_merge(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last,
44210b57cec5SDimitry Andric                _Compare __comp, typename iterator_traits<_BidirectionalIterator>::difference_type __len1,
44220b57cec5SDimitry Andric                                 typename iterator_traits<_BidirectionalIterator>::difference_type __len2,
44230b57cec5SDimitry Andric                typename iterator_traits<_BidirectionalIterator>::value_type* __buff)
44240b57cec5SDimitry Andric{
44250b57cec5SDimitry Andric    typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
44260b57cec5SDimitry Andric    __destruct_n __d(0);
44270b57cec5SDimitry Andric    unique_ptr<value_type, __destruct_n&> __h2(__buff, __d);
44280b57cec5SDimitry Andric    if (__len1 <= __len2)
44290b57cec5SDimitry Andric    {
44300b57cec5SDimitry Andric        value_type* __p = __buff;
4431*e40139ffSDimitry Andric        for (_BidirectionalIterator __i = __first; __i != __middle; __d.__incr((value_type*)0), (void) ++__i, (void) ++__p)
44320b57cec5SDimitry Andric            ::new(__p) value_type(_VSTD::move(*__i));
44330b57cec5SDimitry Andric        __half_inplace_merge(__buff, __p, __middle, __last, __first, __comp);
44340b57cec5SDimitry Andric    }
44350b57cec5SDimitry Andric    else
44360b57cec5SDimitry Andric    {
44370b57cec5SDimitry Andric        value_type* __p = __buff;
4438*e40139ffSDimitry Andric        for (_BidirectionalIterator __i = __middle; __i != __last; __d.__incr((value_type*)0), (void) ++__i, (void) ++__p)
44390b57cec5SDimitry Andric            ::new(__p) value_type(_VSTD::move(*__i));
44400b57cec5SDimitry Andric        typedef reverse_iterator<_BidirectionalIterator> _RBi;
44410b57cec5SDimitry Andric        typedef reverse_iterator<value_type*> _Rv;
44420b57cec5SDimitry Andric        __half_inplace_merge(_Rv(__p), _Rv(__buff),
44430b57cec5SDimitry Andric                             _RBi(__middle), _RBi(__first),
44440b57cec5SDimitry Andric                             _RBi(__last), __invert<_Compare>(__comp));
44450b57cec5SDimitry Andric    }
44460b57cec5SDimitry Andric}
44470b57cec5SDimitry Andric
44480b57cec5SDimitry Andrictemplate <class _Compare, class _BidirectionalIterator>
44490b57cec5SDimitry Andricvoid
44500b57cec5SDimitry Andric__inplace_merge(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last,
44510b57cec5SDimitry Andric                _Compare __comp, typename iterator_traits<_BidirectionalIterator>::difference_type __len1,
44520b57cec5SDimitry Andric                                 typename iterator_traits<_BidirectionalIterator>::difference_type __len2,
44530b57cec5SDimitry Andric                typename iterator_traits<_BidirectionalIterator>::value_type* __buff, ptrdiff_t __buff_size)
44540b57cec5SDimitry Andric{
44550b57cec5SDimitry Andric    typedef typename iterator_traits<_BidirectionalIterator>::difference_type difference_type;
44560b57cec5SDimitry Andric    while (true)
44570b57cec5SDimitry Andric    {
44580b57cec5SDimitry Andric        // if __middle == __last, we're done
44590b57cec5SDimitry Andric        if (__len2 == 0)
44600b57cec5SDimitry Andric            return;
44610b57cec5SDimitry Andric        if (__len1 <= __buff_size || __len2 <= __buff_size)
44620b57cec5SDimitry Andric            return __buffered_inplace_merge<_Compare>
44630b57cec5SDimitry Andric                   (__first, __middle, __last, __comp, __len1, __len2, __buff);
44640b57cec5SDimitry Andric        // shrink [__first, __middle) as much as possible (with no moves), returning if it shrinks to 0
44650b57cec5SDimitry Andric        for (; true; ++__first, (void) --__len1)
44660b57cec5SDimitry Andric        {
44670b57cec5SDimitry Andric            if (__len1 == 0)
44680b57cec5SDimitry Andric                return;
44690b57cec5SDimitry Andric            if (__comp(*__middle, *__first))
44700b57cec5SDimitry Andric                break;
44710b57cec5SDimitry Andric        }
44720b57cec5SDimitry Andric        // __first < __middle < __last
44730b57cec5SDimitry Andric        // *__first > *__middle
44740b57cec5SDimitry Andric        // partition [__first, __m1) [__m1, __middle) [__middle, __m2) [__m2, __last) such that
44750b57cec5SDimitry Andric        //     all elements in:
44760b57cec5SDimitry Andric        //         [__first, __m1)  <= [__middle, __m2)
44770b57cec5SDimitry Andric        //         [__middle, __m2) <  [__m1, __middle)
44780b57cec5SDimitry Andric        //         [__m1, __middle) <= [__m2, __last)
44790b57cec5SDimitry Andric        //     and __m1 or __m2 is in the middle of its range
44800b57cec5SDimitry Andric        _BidirectionalIterator __m1;  // "median" of [__first, __middle)
44810b57cec5SDimitry Andric        _BidirectionalIterator __m2;  // "median" of [__middle, __last)
44820b57cec5SDimitry Andric        difference_type __len11;      // distance(__first, __m1)
44830b57cec5SDimitry Andric        difference_type __len21;      // distance(__middle, __m2)
44840b57cec5SDimitry Andric        // binary search smaller range
44850b57cec5SDimitry Andric        if (__len1 < __len2)
44860b57cec5SDimitry Andric        {   // __len >= 1, __len2 >= 2
44870b57cec5SDimitry Andric            __len21 = __len2 / 2;
44880b57cec5SDimitry Andric            __m2 = __middle;
44890b57cec5SDimitry Andric            _VSTD::advance(__m2, __len21);
44900b57cec5SDimitry Andric            __m1 = __upper_bound<_Compare>(__first, __middle, *__m2, __comp);
44910b57cec5SDimitry Andric            __len11 = _VSTD::distance(__first, __m1);
44920b57cec5SDimitry Andric        }
44930b57cec5SDimitry Andric        else
44940b57cec5SDimitry Andric        {
44950b57cec5SDimitry Andric            if (__len1 == 1)
44960b57cec5SDimitry Andric            {   // __len1 >= __len2 && __len2 > 0, therefore __len2 == 1
44970b57cec5SDimitry Andric                // It is known *__first > *__middle
44980b57cec5SDimitry Andric                swap(*__first, *__middle);
44990b57cec5SDimitry Andric                return;
45000b57cec5SDimitry Andric            }
45010b57cec5SDimitry Andric            // __len1 >= 2, __len2 >= 1
45020b57cec5SDimitry Andric            __len11 = __len1 / 2;
45030b57cec5SDimitry Andric            __m1 = __first;
45040b57cec5SDimitry Andric            _VSTD::advance(__m1, __len11);
45050b57cec5SDimitry Andric            __m2 = __lower_bound<_Compare>(__middle, __last, *__m1, __comp);
45060b57cec5SDimitry Andric            __len21 = _VSTD::distance(__middle, __m2);
45070b57cec5SDimitry Andric        }
45080b57cec5SDimitry Andric        difference_type __len12 = __len1 - __len11;  // distance(__m1, __middle)
45090b57cec5SDimitry Andric        difference_type __len22 = __len2 - __len21;  // distance(__m2, __last)
45100b57cec5SDimitry Andric        // [__first, __m1) [__m1, __middle) [__middle, __m2) [__m2, __last)
45110b57cec5SDimitry Andric        // swap middle two partitions
45120b57cec5SDimitry Andric        __middle = _VSTD::rotate(__m1, __middle, __m2);
45130b57cec5SDimitry Andric        // __len12 and __len21 now have swapped meanings
45140b57cec5SDimitry Andric        // merge smaller range with recurisve call and larger with tail recursion elimination
45150b57cec5SDimitry Andric        if (__len11 + __len21 < __len12 + __len22)
45160b57cec5SDimitry Andric        {
45170b57cec5SDimitry Andric            __inplace_merge<_Compare>(__first, __m1, __middle, __comp, __len11, __len21, __buff, __buff_size);
45180b57cec5SDimitry Andric//          __inplace_merge<_Compare>(__middle, __m2, __last, __comp, __len12, __len22, __buff, __buff_size);
45190b57cec5SDimitry Andric            __first = __middle;
45200b57cec5SDimitry Andric            __middle = __m2;
45210b57cec5SDimitry Andric            __len1 = __len12;
45220b57cec5SDimitry Andric            __len2 = __len22;
45230b57cec5SDimitry Andric        }
45240b57cec5SDimitry Andric        else
45250b57cec5SDimitry Andric        {
45260b57cec5SDimitry Andric            __inplace_merge<_Compare>(__middle, __m2, __last, __comp, __len12, __len22, __buff, __buff_size);
45270b57cec5SDimitry Andric//          __inplace_merge<_Compare>(__first, __m1, __middle, __comp, __len11, __len21, __buff, __buff_size);
45280b57cec5SDimitry Andric            __last = __middle;
45290b57cec5SDimitry Andric            __middle = __m1;
45300b57cec5SDimitry Andric            __len1 = __len11;
45310b57cec5SDimitry Andric            __len2 = __len21;
45320b57cec5SDimitry Andric        }
45330b57cec5SDimitry Andric    }
45340b57cec5SDimitry Andric}
45350b57cec5SDimitry Andric
45360b57cec5SDimitry Andrictemplate <class _BidirectionalIterator, class _Compare>
45370b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
45380b57cec5SDimitry Andricvoid
45390b57cec5SDimitry Andricinplace_merge(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last,
45400b57cec5SDimitry Andric              _Compare __comp)
45410b57cec5SDimitry Andric{
45420b57cec5SDimitry Andric    typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
45430b57cec5SDimitry Andric    typedef typename iterator_traits<_BidirectionalIterator>::difference_type difference_type;
45440b57cec5SDimitry Andric    difference_type __len1 = _VSTD::distance(__first, __middle);
45450b57cec5SDimitry Andric    difference_type __len2 = _VSTD::distance(__middle, __last);
45460b57cec5SDimitry Andric    difference_type __buf_size = _VSTD::min(__len1, __len2);
45470b57cec5SDimitry Andric    pair<value_type*, ptrdiff_t> __buf = _VSTD::get_temporary_buffer<value_type>(__buf_size);
45480b57cec5SDimitry Andric    unique_ptr<value_type, __return_temporary_buffer> __h(__buf.first);
45490b57cec5SDimitry Andric    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
45500b57cec5SDimitry Andric    return _VSTD::__inplace_merge<_Comp_ref>(__first, __middle, __last, __comp, __len1, __len2,
45510b57cec5SDimitry Andric                                            __buf.first, __buf.second);
45520b57cec5SDimitry Andric}
45530b57cec5SDimitry Andric
45540b57cec5SDimitry Andrictemplate <class _BidirectionalIterator>
45550b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
45560b57cec5SDimitry Andricvoid
45570b57cec5SDimitry Andricinplace_merge(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last)
45580b57cec5SDimitry Andric{
45590b57cec5SDimitry Andric    _VSTD::inplace_merge(__first, __middle, __last,
45600b57cec5SDimitry Andric                        __less<typename iterator_traits<_BidirectionalIterator>::value_type>());
45610b57cec5SDimitry Andric}
45620b57cec5SDimitry Andric
45630b57cec5SDimitry Andric// stable_sort
45640b57cec5SDimitry Andric
45650b57cec5SDimitry Andrictemplate <class _Compare, class _InputIterator1, class _InputIterator2>
45660b57cec5SDimitry Andricvoid
45670b57cec5SDimitry Andric__merge_move_construct(_InputIterator1 __first1, _InputIterator1 __last1,
45680b57cec5SDimitry Andric        _InputIterator2 __first2, _InputIterator2 __last2,
45690b57cec5SDimitry Andric        typename iterator_traits<_InputIterator1>::value_type* __result, _Compare __comp)
45700b57cec5SDimitry Andric{
45710b57cec5SDimitry Andric    typedef typename iterator_traits<_InputIterator1>::value_type value_type;
45720b57cec5SDimitry Andric    __destruct_n __d(0);
45730b57cec5SDimitry Andric    unique_ptr<value_type, __destruct_n&> __h(__result, __d);
45740b57cec5SDimitry Andric    for (; true; ++__result)
45750b57cec5SDimitry Andric    {
45760b57cec5SDimitry Andric        if (__first1 == __last1)
45770b57cec5SDimitry Andric        {
4578*e40139ffSDimitry Andric            for (; __first2 != __last2; ++__first2, ++__result, (void) __d.__incr((value_type*)0))
45790b57cec5SDimitry Andric                ::new (__result) value_type(_VSTD::move(*__first2));
45800b57cec5SDimitry Andric            __h.release();
45810b57cec5SDimitry Andric            return;
45820b57cec5SDimitry Andric        }
45830b57cec5SDimitry Andric        if (__first2 == __last2)
45840b57cec5SDimitry Andric        {
4585*e40139ffSDimitry Andric            for (; __first1 != __last1; ++__first1, ++__result, (void) __d.__incr((value_type*)0))
45860b57cec5SDimitry Andric                ::new (__result) value_type(_VSTD::move(*__first1));
45870b57cec5SDimitry Andric            __h.release();
45880b57cec5SDimitry Andric            return;
45890b57cec5SDimitry Andric        }
45900b57cec5SDimitry Andric        if (__comp(*__first2, *__first1))
45910b57cec5SDimitry Andric        {
45920b57cec5SDimitry Andric            ::new (__result) value_type(_VSTD::move(*__first2));
45930b57cec5SDimitry Andric            __d.__incr((value_type*)0);
45940b57cec5SDimitry Andric            ++__first2;
45950b57cec5SDimitry Andric        }
45960b57cec5SDimitry Andric        else
45970b57cec5SDimitry Andric        {
45980b57cec5SDimitry Andric            ::new (__result) value_type(_VSTD::move(*__first1));
45990b57cec5SDimitry Andric            __d.__incr((value_type*)0);
46000b57cec5SDimitry Andric            ++__first1;
46010b57cec5SDimitry Andric        }
46020b57cec5SDimitry Andric    }
46030b57cec5SDimitry Andric}
46040b57cec5SDimitry Andric
46050b57cec5SDimitry Andrictemplate <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
46060b57cec5SDimitry Andricvoid
46070b57cec5SDimitry Andric__merge_move_assign(_InputIterator1 __first1, _InputIterator1 __last1,
46080b57cec5SDimitry Andric        _InputIterator2 __first2, _InputIterator2 __last2,
46090b57cec5SDimitry Andric        _OutputIterator __result, _Compare __comp)
46100b57cec5SDimitry Andric{
46110b57cec5SDimitry Andric    for (; __first1 != __last1; ++__result)
46120b57cec5SDimitry Andric    {
46130b57cec5SDimitry Andric        if (__first2 == __last2)
46140b57cec5SDimitry Andric        {
4615*e40139ffSDimitry Andric            for (; __first1 != __last1; ++__first1, (void) ++__result)
46160b57cec5SDimitry Andric                *__result = _VSTD::move(*__first1);
46170b57cec5SDimitry Andric            return;
46180b57cec5SDimitry Andric        }
46190b57cec5SDimitry Andric        if (__comp(*__first2, *__first1))
46200b57cec5SDimitry Andric        {
46210b57cec5SDimitry Andric            *__result = _VSTD::move(*__first2);
46220b57cec5SDimitry Andric            ++__first2;
46230b57cec5SDimitry Andric        }
46240b57cec5SDimitry Andric        else
46250b57cec5SDimitry Andric        {
46260b57cec5SDimitry Andric            *__result = _VSTD::move(*__first1);
46270b57cec5SDimitry Andric            ++__first1;
46280b57cec5SDimitry Andric        }
46290b57cec5SDimitry Andric    }
4630*e40139ffSDimitry Andric    for (; __first2 != __last2; ++__first2, (void) ++__result)
46310b57cec5SDimitry Andric        *__result = _VSTD::move(*__first2);
46320b57cec5SDimitry Andric}
46330b57cec5SDimitry Andric
46340b57cec5SDimitry Andrictemplate <class _Compare, class _RandomAccessIterator>
46350b57cec5SDimitry Andricvoid
46360b57cec5SDimitry Andric__stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp,
46370b57cec5SDimitry Andric              typename iterator_traits<_RandomAccessIterator>::difference_type __len,
46380b57cec5SDimitry Andric              typename iterator_traits<_RandomAccessIterator>::value_type* __buff, ptrdiff_t __buff_size);
46390b57cec5SDimitry Andric
46400b57cec5SDimitry Andrictemplate <class _Compare, class _RandomAccessIterator>
46410b57cec5SDimitry Andricvoid
46420b57cec5SDimitry Andric__stable_sort_move(_RandomAccessIterator __first1, _RandomAccessIterator __last1, _Compare __comp,
46430b57cec5SDimitry Andric                   typename iterator_traits<_RandomAccessIterator>::difference_type __len,
46440b57cec5SDimitry Andric                   typename iterator_traits<_RandomAccessIterator>::value_type* __first2)
46450b57cec5SDimitry Andric{
46460b57cec5SDimitry Andric    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
46470b57cec5SDimitry Andric    switch (__len)
46480b57cec5SDimitry Andric    {
46490b57cec5SDimitry Andric    case 0:
46500b57cec5SDimitry Andric        return;
46510b57cec5SDimitry Andric    case 1:
46520b57cec5SDimitry Andric        ::new(__first2) value_type(_VSTD::move(*__first1));
46530b57cec5SDimitry Andric        return;
46540b57cec5SDimitry Andric    case 2:
46550b57cec5SDimitry Andric        __destruct_n __d(0);
46560b57cec5SDimitry Andric        unique_ptr<value_type, __destruct_n&> __h2(__first2, __d);
46570b57cec5SDimitry Andric        if (__comp(*--__last1, *__first1))
46580b57cec5SDimitry Andric        {
46590b57cec5SDimitry Andric            ::new(__first2) value_type(_VSTD::move(*__last1));
46600b57cec5SDimitry Andric            __d.__incr((value_type*)0);
46610b57cec5SDimitry Andric            ++__first2;
46620b57cec5SDimitry Andric            ::new(__first2) value_type(_VSTD::move(*__first1));
46630b57cec5SDimitry Andric        }
46640b57cec5SDimitry Andric        else
46650b57cec5SDimitry Andric        {
46660b57cec5SDimitry Andric            ::new(__first2) value_type(_VSTD::move(*__first1));
46670b57cec5SDimitry Andric            __d.__incr((value_type*)0);
46680b57cec5SDimitry Andric            ++__first2;
46690b57cec5SDimitry Andric            ::new(__first2) value_type(_VSTD::move(*__last1));
46700b57cec5SDimitry Andric        }
46710b57cec5SDimitry Andric        __h2.release();
46720b57cec5SDimitry Andric        return;
46730b57cec5SDimitry Andric    }
46740b57cec5SDimitry Andric    if (__len <= 8)
46750b57cec5SDimitry Andric    {
46760b57cec5SDimitry Andric        __insertion_sort_move<_Compare>(__first1, __last1, __first2, __comp);
46770b57cec5SDimitry Andric        return;
46780b57cec5SDimitry Andric    }
46790b57cec5SDimitry Andric    typename iterator_traits<_RandomAccessIterator>::difference_type __l2 = __len / 2;
46800b57cec5SDimitry Andric    _RandomAccessIterator __m = __first1 + __l2;
46810b57cec5SDimitry Andric    __stable_sort<_Compare>(__first1, __m, __comp, __l2, __first2, __l2);
46820b57cec5SDimitry Andric    __stable_sort<_Compare>(__m, __last1, __comp, __len - __l2, __first2 + __l2, __len - __l2);
46830b57cec5SDimitry Andric    __merge_move_construct<_Compare>(__first1, __m, __m, __last1, __first2, __comp);
46840b57cec5SDimitry Andric}
46850b57cec5SDimitry Andric
46860b57cec5SDimitry Andrictemplate <class _Tp>
46870b57cec5SDimitry Andricstruct __stable_sort_switch
46880b57cec5SDimitry Andric{
46890b57cec5SDimitry Andric    static const unsigned value = 128*is_trivially_copy_assignable<_Tp>::value;
46900b57cec5SDimitry Andric};
46910b57cec5SDimitry Andric
46920b57cec5SDimitry Andrictemplate <class _Compare, class _RandomAccessIterator>
46930b57cec5SDimitry Andricvoid
46940b57cec5SDimitry Andric__stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp,
46950b57cec5SDimitry Andric              typename iterator_traits<_RandomAccessIterator>::difference_type __len,
46960b57cec5SDimitry Andric              typename iterator_traits<_RandomAccessIterator>::value_type* __buff, ptrdiff_t __buff_size)
46970b57cec5SDimitry Andric{
46980b57cec5SDimitry Andric    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
46990b57cec5SDimitry Andric    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
47000b57cec5SDimitry Andric    switch (__len)
47010b57cec5SDimitry Andric    {
47020b57cec5SDimitry Andric    case 0:
47030b57cec5SDimitry Andric    case 1:
47040b57cec5SDimitry Andric        return;
47050b57cec5SDimitry Andric    case 2:
47060b57cec5SDimitry Andric        if (__comp(*--__last, *__first))
47070b57cec5SDimitry Andric            swap(*__first, *__last);
47080b57cec5SDimitry Andric        return;
47090b57cec5SDimitry Andric    }
47100b57cec5SDimitry Andric    if (__len <= static_cast<difference_type>(__stable_sort_switch<value_type>::value))
47110b57cec5SDimitry Andric    {
47120b57cec5SDimitry Andric        __insertion_sort<_Compare>(__first, __last, __comp);
47130b57cec5SDimitry Andric        return;
47140b57cec5SDimitry Andric    }
47150b57cec5SDimitry Andric    typename iterator_traits<_RandomAccessIterator>::difference_type __l2 = __len / 2;
47160b57cec5SDimitry Andric    _RandomAccessIterator __m = __first + __l2;
47170b57cec5SDimitry Andric    if (__len <= __buff_size)
47180b57cec5SDimitry Andric    {
47190b57cec5SDimitry Andric        __destruct_n __d(0);
47200b57cec5SDimitry Andric        unique_ptr<value_type, __destruct_n&> __h2(__buff, __d);
47210b57cec5SDimitry Andric        __stable_sort_move<_Compare>(__first, __m, __comp, __l2, __buff);
47220b57cec5SDimitry Andric        __d.__set(__l2, (value_type*)0);
47230b57cec5SDimitry Andric        __stable_sort_move<_Compare>(__m, __last, __comp, __len - __l2, __buff + __l2);
47240b57cec5SDimitry Andric        __d.__set(__len, (value_type*)0);
47250b57cec5SDimitry Andric        __merge_move_assign<_Compare>(__buff, __buff + __l2, __buff + __l2, __buff + __len, __first, __comp);
47260b57cec5SDimitry Andric//         __merge<_Compare>(move_iterator<value_type*>(__buff),
47270b57cec5SDimitry Andric//                           move_iterator<value_type*>(__buff + __l2),
47280b57cec5SDimitry Andric//                           move_iterator<_RandomAccessIterator>(__buff + __l2),
47290b57cec5SDimitry Andric//                           move_iterator<_RandomAccessIterator>(__buff + __len),
47300b57cec5SDimitry Andric//                           __first, __comp);
47310b57cec5SDimitry Andric        return;
47320b57cec5SDimitry Andric    }
47330b57cec5SDimitry Andric    __stable_sort<_Compare>(__first, __m, __comp, __l2, __buff, __buff_size);
47340b57cec5SDimitry Andric    __stable_sort<_Compare>(__m, __last, __comp, __len - __l2, __buff, __buff_size);
47350b57cec5SDimitry Andric    __inplace_merge<_Compare>(__first, __m, __last, __comp, __l2, __len - __l2, __buff, __buff_size);
47360b57cec5SDimitry Andric}
47370b57cec5SDimitry Andric
47380b57cec5SDimitry Andrictemplate <class _RandomAccessIterator, class _Compare>
47390b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
47400b57cec5SDimitry Andricvoid
47410b57cec5SDimitry Andricstable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
47420b57cec5SDimitry Andric{
47430b57cec5SDimitry Andric    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
47440b57cec5SDimitry Andric    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
47450b57cec5SDimitry Andric    difference_type __len = __last - __first;
47460b57cec5SDimitry Andric    pair<value_type*, ptrdiff_t> __buf(0, 0);
47470b57cec5SDimitry Andric    unique_ptr<value_type, __return_temporary_buffer> __h;
47480b57cec5SDimitry Andric    if (__len > static_cast<difference_type>(__stable_sort_switch<value_type>::value))
47490b57cec5SDimitry Andric    {
47500b57cec5SDimitry Andric        __buf = _VSTD::get_temporary_buffer<value_type>(__len);
47510b57cec5SDimitry Andric        __h.reset(__buf.first);
47520b57cec5SDimitry Andric    }
47530b57cec5SDimitry Andric    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
47540b57cec5SDimitry Andric    __stable_sort<_Comp_ref>(__first, __last, __comp, __len, __buf.first, __buf.second);
47550b57cec5SDimitry Andric}
47560b57cec5SDimitry Andric
47570b57cec5SDimitry Andrictemplate <class _RandomAccessIterator>
47580b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
47590b57cec5SDimitry Andricvoid
47600b57cec5SDimitry Andricstable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last)
47610b57cec5SDimitry Andric{
47620b57cec5SDimitry Andric    _VSTD::stable_sort(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
47630b57cec5SDimitry Andric}
47640b57cec5SDimitry Andric
47650b57cec5SDimitry Andric// is_heap_until
47660b57cec5SDimitry Andric
47670b57cec5SDimitry Andrictemplate <class _RandomAccessIterator, class _Compare>
47680b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _RandomAccessIterator
47690b57cec5SDimitry Andricis_heap_until(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
47700b57cec5SDimitry Andric{
47710b57cec5SDimitry Andric    typedef typename _VSTD::iterator_traits<_RandomAccessIterator>::difference_type difference_type;
47720b57cec5SDimitry Andric    difference_type __len = __last - __first;
47730b57cec5SDimitry Andric    difference_type __p = 0;
47740b57cec5SDimitry Andric    difference_type __c = 1;
47750b57cec5SDimitry Andric    _RandomAccessIterator __pp = __first;
47760b57cec5SDimitry Andric    while (__c < __len)
47770b57cec5SDimitry Andric    {
47780b57cec5SDimitry Andric        _RandomAccessIterator __cp = __first + __c;
47790b57cec5SDimitry Andric        if (__comp(*__pp, *__cp))
47800b57cec5SDimitry Andric            return __cp;
47810b57cec5SDimitry Andric        ++__c;
47820b57cec5SDimitry Andric        ++__cp;
47830b57cec5SDimitry Andric        if (__c == __len)
47840b57cec5SDimitry Andric            return __last;
47850b57cec5SDimitry Andric        if (__comp(*__pp, *__cp))
47860b57cec5SDimitry Andric            return __cp;
47870b57cec5SDimitry Andric        ++__p;
47880b57cec5SDimitry Andric        ++__pp;
47890b57cec5SDimitry Andric        __c = 2 * __p + 1;
47900b57cec5SDimitry Andric    }
47910b57cec5SDimitry Andric    return __last;
47920b57cec5SDimitry Andric}
47930b57cec5SDimitry Andric
47940b57cec5SDimitry Andrictemplate<class _RandomAccessIterator>
47950b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
47960b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
47970b57cec5SDimitry Andric_RandomAccessIterator
47980b57cec5SDimitry Andricis_heap_until(_RandomAccessIterator __first, _RandomAccessIterator __last)
47990b57cec5SDimitry Andric{
48000b57cec5SDimitry Andric    return _VSTD::is_heap_until(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
48010b57cec5SDimitry Andric}
48020b57cec5SDimitry Andric
48030b57cec5SDimitry Andric// is_heap
48040b57cec5SDimitry Andric
48050b57cec5SDimitry Andrictemplate <class _RandomAccessIterator, class _Compare>
48060b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
48070b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
48080b57cec5SDimitry Andricbool
48090b57cec5SDimitry Andricis_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
48100b57cec5SDimitry Andric{
48110b57cec5SDimitry Andric    return _VSTD::is_heap_until(__first, __last, __comp) == __last;
48120b57cec5SDimitry Andric}
48130b57cec5SDimitry Andric
48140b57cec5SDimitry Andrictemplate<class _RandomAccessIterator>
48150b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
48160b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
48170b57cec5SDimitry Andricbool
48180b57cec5SDimitry Andricis_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
48190b57cec5SDimitry Andric{
48200b57cec5SDimitry Andric    return _VSTD::is_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
48210b57cec5SDimitry Andric}
48220b57cec5SDimitry Andric
48230b57cec5SDimitry Andric// push_heap
48240b57cec5SDimitry Andric
48250b57cec5SDimitry Andrictemplate <class _Compare, class _RandomAccessIterator>
48260b57cec5SDimitry Andricvoid
48270b57cec5SDimitry Andric__sift_up(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp,
48280b57cec5SDimitry Andric          typename iterator_traits<_RandomAccessIterator>::difference_type __len)
48290b57cec5SDimitry Andric{
48300b57cec5SDimitry Andric    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
48310b57cec5SDimitry Andric    if (__len > 1)
48320b57cec5SDimitry Andric    {
48330b57cec5SDimitry Andric        __len = (__len - 2) / 2;
48340b57cec5SDimitry Andric        _RandomAccessIterator __ptr = __first + __len;
48350b57cec5SDimitry Andric        if (__comp(*__ptr, *--__last))
48360b57cec5SDimitry Andric        {
48370b57cec5SDimitry Andric            value_type __t(_VSTD::move(*__last));
48380b57cec5SDimitry Andric            do
48390b57cec5SDimitry Andric            {
48400b57cec5SDimitry Andric                *__last = _VSTD::move(*__ptr);
48410b57cec5SDimitry Andric                __last = __ptr;
48420b57cec5SDimitry Andric                if (__len == 0)
48430b57cec5SDimitry Andric                    break;
48440b57cec5SDimitry Andric                __len = (__len - 1) / 2;
48450b57cec5SDimitry Andric                __ptr = __first + __len;
48460b57cec5SDimitry Andric            } while (__comp(*__ptr, __t));
48470b57cec5SDimitry Andric            *__last = _VSTD::move(__t);
48480b57cec5SDimitry Andric        }
48490b57cec5SDimitry Andric    }
48500b57cec5SDimitry Andric}
48510b57cec5SDimitry Andric
48520b57cec5SDimitry Andrictemplate <class _RandomAccessIterator, class _Compare>
48530b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
48540b57cec5SDimitry Andricvoid
48550b57cec5SDimitry Andricpush_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
48560b57cec5SDimitry Andric{
48570b57cec5SDimitry Andric    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
48580b57cec5SDimitry Andric    __sift_up<_Comp_ref>(__first, __last, __comp, __last - __first);
48590b57cec5SDimitry Andric}
48600b57cec5SDimitry Andric
48610b57cec5SDimitry Andrictemplate <class _RandomAccessIterator>
48620b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
48630b57cec5SDimitry Andricvoid
48640b57cec5SDimitry Andricpush_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
48650b57cec5SDimitry Andric{
48660b57cec5SDimitry Andric    _VSTD::push_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
48670b57cec5SDimitry Andric}
48680b57cec5SDimitry Andric
48690b57cec5SDimitry Andric// pop_heap
48700b57cec5SDimitry Andric
48710b57cec5SDimitry Andrictemplate <class _Compare, class _RandomAccessIterator>
48720b57cec5SDimitry Andricvoid
48730b57cec5SDimitry Andric__sift_down(_RandomAccessIterator __first, _RandomAccessIterator /*__last*/,
48740b57cec5SDimitry Andric            _Compare __comp,
48750b57cec5SDimitry Andric            typename iterator_traits<_RandomAccessIterator>::difference_type __len,
48760b57cec5SDimitry Andric            _RandomAccessIterator __start)
48770b57cec5SDimitry Andric{
48780b57cec5SDimitry Andric    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
48790b57cec5SDimitry Andric    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
48800b57cec5SDimitry Andric    // left-child of __start is at 2 * __start + 1
48810b57cec5SDimitry Andric    // right-child of __start is at 2 * __start + 2
48820b57cec5SDimitry Andric    difference_type __child = __start - __first;
48830b57cec5SDimitry Andric
48840b57cec5SDimitry Andric    if (__len < 2 || (__len - 2) / 2 < __child)
48850b57cec5SDimitry Andric        return;
48860b57cec5SDimitry Andric
48870b57cec5SDimitry Andric    __child = 2 * __child + 1;
48880b57cec5SDimitry Andric    _RandomAccessIterator __child_i = __first + __child;
48890b57cec5SDimitry Andric
48900b57cec5SDimitry Andric    if ((__child + 1) < __len && __comp(*__child_i, *(__child_i + 1))) {
48910b57cec5SDimitry Andric        // right-child exists and is greater than left-child
48920b57cec5SDimitry Andric        ++__child_i;
48930b57cec5SDimitry Andric        ++__child;
48940b57cec5SDimitry Andric    }
48950b57cec5SDimitry Andric
48960b57cec5SDimitry Andric    // check if we are in heap-order
48970b57cec5SDimitry Andric    if (__comp(*__child_i, *__start))
48980b57cec5SDimitry Andric        // we are, __start is larger than it's largest child
48990b57cec5SDimitry Andric        return;
49000b57cec5SDimitry Andric
49010b57cec5SDimitry Andric    value_type __top(_VSTD::move(*__start));
49020b57cec5SDimitry Andric    do
49030b57cec5SDimitry Andric    {
49040b57cec5SDimitry Andric        // we are not in heap-order, swap the parent with it's largest child
49050b57cec5SDimitry Andric        *__start = _VSTD::move(*__child_i);
49060b57cec5SDimitry Andric        __start = __child_i;
49070b57cec5SDimitry Andric
49080b57cec5SDimitry Andric        if ((__len - 2) / 2 < __child)
49090b57cec5SDimitry Andric            break;
49100b57cec5SDimitry Andric
49110b57cec5SDimitry Andric        // recompute the child based off of the updated parent
49120b57cec5SDimitry Andric        __child = 2 * __child + 1;
49130b57cec5SDimitry Andric        __child_i = __first + __child;
49140b57cec5SDimitry Andric
49150b57cec5SDimitry Andric        if ((__child + 1) < __len && __comp(*__child_i, *(__child_i + 1))) {
49160b57cec5SDimitry Andric            // right-child exists and is greater than left-child
49170b57cec5SDimitry Andric            ++__child_i;
49180b57cec5SDimitry Andric            ++__child;
49190b57cec5SDimitry Andric        }
49200b57cec5SDimitry Andric
49210b57cec5SDimitry Andric        // check if we are in heap-order
49220b57cec5SDimitry Andric    } while (!__comp(*__child_i, __top));
49230b57cec5SDimitry Andric    *__start = _VSTD::move(__top);
49240b57cec5SDimitry Andric}
49250b57cec5SDimitry Andric
49260b57cec5SDimitry Andrictemplate <class _Compare, class _RandomAccessIterator>
49270b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
49280b57cec5SDimitry Andricvoid
49290b57cec5SDimitry Andric__pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp,
49300b57cec5SDimitry Andric           typename iterator_traits<_RandomAccessIterator>::difference_type __len)
49310b57cec5SDimitry Andric{
49320b57cec5SDimitry Andric    if (__len > 1)
49330b57cec5SDimitry Andric    {
49340b57cec5SDimitry Andric        swap(*__first, *--__last);
49350b57cec5SDimitry Andric        __sift_down<_Compare>(__first, __last, __comp, __len - 1, __first);
49360b57cec5SDimitry Andric    }
49370b57cec5SDimitry Andric}
49380b57cec5SDimitry Andric
49390b57cec5SDimitry Andrictemplate <class _RandomAccessIterator, class _Compare>
49400b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
49410b57cec5SDimitry Andricvoid
49420b57cec5SDimitry Andricpop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
49430b57cec5SDimitry Andric{
49440b57cec5SDimitry Andric    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
49450b57cec5SDimitry Andric    __pop_heap<_Comp_ref>(__first, __last, __comp, __last - __first);
49460b57cec5SDimitry Andric}
49470b57cec5SDimitry Andric
49480b57cec5SDimitry Andrictemplate <class _RandomAccessIterator>
49490b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
49500b57cec5SDimitry Andricvoid
49510b57cec5SDimitry Andricpop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
49520b57cec5SDimitry Andric{
49530b57cec5SDimitry Andric    _VSTD::pop_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
49540b57cec5SDimitry Andric}
49550b57cec5SDimitry Andric
49560b57cec5SDimitry Andric// make_heap
49570b57cec5SDimitry Andric
49580b57cec5SDimitry Andrictemplate <class _Compare, class _RandomAccessIterator>
49590b57cec5SDimitry Andricvoid
49600b57cec5SDimitry Andric__make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
49610b57cec5SDimitry Andric{
49620b57cec5SDimitry Andric    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
49630b57cec5SDimitry Andric    difference_type __n = __last - __first;
49640b57cec5SDimitry Andric    if (__n > 1)
49650b57cec5SDimitry Andric    {
49660b57cec5SDimitry Andric        // start from the first parent, there is no need to consider children
49670b57cec5SDimitry Andric        for (difference_type __start = (__n - 2) / 2; __start >= 0; --__start)
49680b57cec5SDimitry Andric        {
49690b57cec5SDimitry Andric            __sift_down<_Compare>(__first, __last, __comp, __n, __first + __start);
49700b57cec5SDimitry Andric        }
49710b57cec5SDimitry Andric    }
49720b57cec5SDimitry Andric}
49730b57cec5SDimitry Andric
49740b57cec5SDimitry Andrictemplate <class _RandomAccessIterator, class _Compare>
49750b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
49760b57cec5SDimitry Andricvoid
49770b57cec5SDimitry Andricmake_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
49780b57cec5SDimitry Andric{
49790b57cec5SDimitry Andric    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
49800b57cec5SDimitry Andric    __make_heap<_Comp_ref>(__first, __last, __comp);
49810b57cec5SDimitry Andric}
49820b57cec5SDimitry Andric
49830b57cec5SDimitry Andrictemplate <class _RandomAccessIterator>
49840b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
49850b57cec5SDimitry Andricvoid
49860b57cec5SDimitry Andricmake_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
49870b57cec5SDimitry Andric{
49880b57cec5SDimitry Andric    _VSTD::make_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
49890b57cec5SDimitry Andric}
49900b57cec5SDimitry Andric
49910b57cec5SDimitry Andric// sort_heap
49920b57cec5SDimitry Andric
49930b57cec5SDimitry Andrictemplate <class _Compare, class _RandomAccessIterator>
49940b57cec5SDimitry Andricvoid
49950b57cec5SDimitry Andric__sort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
49960b57cec5SDimitry Andric{
49970b57cec5SDimitry Andric    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
4998*e40139ffSDimitry Andric    for (difference_type __n = __last - __first; __n > 1; --__last, (void) --__n)
49990b57cec5SDimitry Andric        __pop_heap<_Compare>(__first, __last, __comp, __n);
50000b57cec5SDimitry Andric}
50010b57cec5SDimitry Andric
50020b57cec5SDimitry Andrictemplate <class _RandomAccessIterator, class _Compare>
50030b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
50040b57cec5SDimitry Andricvoid
50050b57cec5SDimitry Andricsort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
50060b57cec5SDimitry Andric{
50070b57cec5SDimitry Andric    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
50080b57cec5SDimitry Andric    __sort_heap<_Comp_ref>(__first, __last, __comp);
50090b57cec5SDimitry Andric}
50100b57cec5SDimitry Andric
50110b57cec5SDimitry Andrictemplate <class _RandomAccessIterator>
50120b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
50130b57cec5SDimitry Andricvoid
50140b57cec5SDimitry Andricsort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
50150b57cec5SDimitry Andric{
50160b57cec5SDimitry Andric    _VSTD::sort_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
50170b57cec5SDimitry Andric}
50180b57cec5SDimitry Andric
50190b57cec5SDimitry Andric// partial_sort
50200b57cec5SDimitry Andric
50210b57cec5SDimitry Andrictemplate <class _Compare, class _RandomAccessIterator>
50220b57cec5SDimitry Andricvoid
50230b57cec5SDimitry Andric__partial_sort(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last,
50240b57cec5SDimitry Andric             _Compare __comp)
50250b57cec5SDimitry Andric{
50260b57cec5SDimitry Andric    __make_heap<_Compare>(__first, __middle, __comp);
50270b57cec5SDimitry Andric    typename iterator_traits<_RandomAccessIterator>::difference_type __len = __middle - __first;
50280b57cec5SDimitry Andric    for (_RandomAccessIterator __i = __middle; __i != __last; ++__i)
50290b57cec5SDimitry Andric    {
50300b57cec5SDimitry Andric        if (__comp(*__i, *__first))
50310b57cec5SDimitry Andric        {
50320b57cec5SDimitry Andric            swap(*__i, *__first);
50330b57cec5SDimitry Andric            __sift_down<_Compare>(__first, __middle, __comp, __len, __first);
50340b57cec5SDimitry Andric        }
50350b57cec5SDimitry Andric    }
50360b57cec5SDimitry Andric    __sort_heap<_Compare>(__first, __middle, __comp);
50370b57cec5SDimitry Andric}
50380b57cec5SDimitry Andric
50390b57cec5SDimitry Andrictemplate <class _RandomAccessIterator, class _Compare>
50400b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
50410b57cec5SDimitry Andricvoid
50420b57cec5SDimitry Andricpartial_sort(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last,
50430b57cec5SDimitry Andric             _Compare __comp)
50440b57cec5SDimitry Andric{
50450b57cec5SDimitry Andric    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
50460b57cec5SDimitry Andric    __partial_sort<_Comp_ref>(__first, __middle, __last, __comp);
50470b57cec5SDimitry Andric}
50480b57cec5SDimitry Andric
50490b57cec5SDimitry Andrictemplate <class _RandomAccessIterator>
50500b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
50510b57cec5SDimitry Andricvoid
50520b57cec5SDimitry Andricpartial_sort(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last)
50530b57cec5SDimitry Andric{
50540b57cec5SDimitry Andric    _VSTD::partial_sort(__first, __middle, __last,
50550b57cec5SDimitry Andric                       __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
50560b57cec5SDimitry Andric}
50570b57cec5SDimitry Andric
50580b57cec5SDimitry Andric// partial_sort_copy
50590b57cec5SDimitry Andric
50600b57cec5SDimitry Andrictemplate <class _Compare, class _InputIterator, class _RandomAccessIterator>
50610b57cec5SDimitry Andric_RandomAccessIterator
50620b57cec5SDimitry Andric__partial_sort_copy(_InputIterator __first, _InputIterator __last,
50630b57cec5SDimitry Andric                    _RandomAccessIterator __result_first, _RandomAccessIterator __result_last, _Compare __comp)
50640b57cec5SDimitry Andric{
50650b57cec5SDimitry Andric    _RandomAccessIterator __r = __result_first;
50660b57cec5SDimitry Andric    if (__r != __result_last)
50670b57cec5SDimitry Andric    {
5068*e40139ffSDimitry Andric        for (; __first != __last && __r != __result_last; ++__first, (void) ++__r)
50690b57cec5SDimitry Andric            *__r = *__first;
50700b57cec5SDimitry Andric        __make_heap<_Compare>(__result_first, __r, __comp);
50710b57cec5SDimitry Andric        typename iterator_traits<_RandomAccessIterator>::difference_type __len = __r - __result_first;
50720b57cec5SDimitry Andric        for (; __first != __last; ++__first)
50730b57cec5SDimitry Andric            if (__comp(*__first, *__result_first))
50740b57cec5SDimitry Andric            {
50750b57cec5SDimitry Andric                *__result_first = *__first;
50760b57cec5SDimitry Andric                __sift_down<_Compare>(__result_first, __r, __comp, __len, __result_first);
50770b57cec5SDimitry Andric            }
50780b57cec5SDimitry Andric        __sort_heap<_Compare>(__result_first, __r, __comp);
50790b57cec5SDimitry Andric    }
50800b57cec5SDimitry Andric    return __r;
50810b57cec5SDimitry Andric}
50820b57cec5SDimitry Andric
50830b57cec5SDimitry Andrictemplate <class _InputIterator, class _RandomAccessIterator, class _Compare>
50840b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
50850b57cec5SDimitry Andric_RandomAccessIterator
50860b57cec5SDimitry Andricpartial_sort_copy(_InputIterator __first, _InputIterator __last,
50870b57cec5SDimitry Andric                  _RandomAccessIterator __result_first, _RandomAccessIterator __result_last, _Compare __comp)
50880b57cec5SDimitry Andric{
50890b57cec5SDimitry Andric    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
50900b57cec5SDimitry Andric    return __partial_sort_copy<_Comp_ref>(__first, __last, __result_first, __result_last, __comp);
50910b57cec5SDimitry Andric}
50920b57cec5SDimitry Andric
50930b57cec5SDimitry Andrictemplate <class _InputIterator, class _RandomAccessIterator>
50940b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
50950b57cec5SDimitry Andric_RandomAccessIterator
50960b57cec5SDimitry Andricpartial_sort_copy(_InputIterator __first, _InputIterator __last,
50970b57cec5SDimitry Andric                  _RandomAccessIterator __result_first, _RandomAccessIterator __result_last)
50980b57cec5SDimitry Andric{
50990b57cec5SDimitry Andric    return _VSTD::partial_sort_copy(__first, __last, __result_first, __result_last,
51000b57cec5SDimitry Andric                                   __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
51010b57cec5SDimitry Andric}
51020b57cec5SDimitry Andric
51030b57cec5SDimitry Andric// nth_element
51040b57cec5SDimitry Andric
51050b57cec5SDimitry Andrictemplate <class _Compare, class _RandomAccessIterator>
51060b57cec5SDimitry Andricvoid
51070b57cec5SDimitry Andric__nth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth, _RandomAccessIterator __last, _Compare __comp)
51080b57cec5SDimitry Andric{
51090b57cec5SDimitry Andric    // _Compare is known to be a reference type
51100b57cec5SDimitry Andric    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
51110b57cec5SDimitry Andric    const difference_type __limit = 7;
51120b57cec5SDimitry Andric    while (true)
51130b57cec5SDimitry Andric    {
51140b57cec5SDimitry Andric    __restart:
51150b57cec5SDimitry Andric        if (__nth == __last)
51160b57cec5SDimitry Andric            return;
51170b57cec5SDimitry Andric        difference_type __len = __last - __first;
51180b57cec5SDimitry Andric        switch (__len)
51190b57cec5SDimitry Andric        {
51200b57cec5SDimitry Andric        case 0:
51210b57cec5SDimitry Andric        case 1:
51220b57cec5SDimitry Andric            return;
51230b57cec5SDimitry Andric        case 2:
51240b57cec5SDimitry Andric            if (__comp(*--__last, *__first))
51250b57cec5SDimitry Andric                swap(*__first, *__last);
51260b57cec5SDimitry Andric            return;
51270b57cec5SDimitry Andric        case 3:
51280b57cec5SDimitry Andric            {
51290b57cec5SDimitry Andric            _RandomAccessIterator __m = __first;
51300b57cec5SDimitry Andric            _VSTD::__sort3<_Compare>(__first, ++__m, --__last, __comp);
51310b57cec5SDimitry Andric            return;
51320b57cec5SDimitry Andric            }
51330b57cec5SDimitry Andric        }
51340b57cec5SDimitry Andric        if (__len <= __limit)
51350b57cec5SDimitry Andric        {
51360b57cec5SDimitry Andric            __selection_sort<_Compare>(__first, __last, __comp);
51370b57cec5SDimitry Andric            return;
51380b57cec5SDimitry Andric        }
51390b57cec5SDimitry Andric        // __len > __limit >= 3
51400b57cec5SDimitry Andric        _RandomAccessIterator __m = __first + __len/2;
51410b57cec5SDimitry Andric        _RandomAccessIterator __lm1 = __last;
51420b57cec5SDimitry Andric        unsigned __n_swaps = _VSTD::__sort3<_Compare>(__first, __m, --__lm1, __comp);
51430b57cec5SDimitry Andric        // *__m is median
51440b57cec5SDimitry Andric        // partition [__first, __m) < *__m and *__m <= [__m, __last)
51450b57cec5SDimitry Andric        // (this inhibits tossing elements equivalent to __m around unnecessarily)
51460b57cec5SDimitry Andric        _RandomAccessIterator __i = __first;
51470b57cec5SDimitry Andric        _RandomAccessIterator __j = __lm1;
51480b57cec5SDimitry Andric        // j points beyond range to be tested, *__lm1 is known to be <= *__m
51490b57cec5SDimitry Andric        // The search going up is known to be guarded but the search coming down isn't.
51500b57cec5SDimitry Andric        // Prime the downward search with a guard.
51510b57cec5SDimitry Andric        if (!__comp(*__i, *__m))  // if *__first == *__m
51520b57cec5SDimitry Andric        {
51530b57cec5SDimitry Andric            // *__first == *__m, *__first doesn't go in first part
51540b57cec5SDimitry Andric            // manually guard downward moving __j against __i
51550b57cec5SDimitry Andric            while (true)
51560b57cec5SDimitry Andric            {
51570b57cec5SDimitry Andric                if (__i == --__j)
51580b57cec5SDimitry Andric                {
51590b57cec5SDimitry Andric                    // *__first == *__m, *__m <= all other elements
51600b57cec5SDimitry Andric                    // Parition instead into [__first, __i) == *__first and *__first < [__i, __last)
51610b57cec5SDimitry Andric                    ++__i;  // __first + 1
51620b57cec5SDimitry Andric                    __j = __last;
51630b57cec5SDimitry Andric                    if (!__comp(*__first, *--__j))  // we need a guard if *__first == *(__last-1)
51640b57cec5SDimitry Andric                    {
51650b57cec5SDimitry Andric                        while (true)
51660b57cec5SDimitry Andric                        {
51670b57cec5SDimitry Andric                            if (__i == __j)
51680b57cec5SDimitry Andric                                return;  // [__first, __last) all equivalent elements
51690b57cec5SDimitry Andric                            if (__comp(*__first, *__i))
51700b57cec5SDimitry Andric                            {
51710b57cec5SDimitry Andric                                swap(*__i, *__j);
51720b57cec5SDimitry Andric                                ++__n_swaps;
51730b57cec5SDimitry Andric                                ++__i;
51740b57cec5SDimitry Andric                                break;
51750b57cec5SDimitry Andric                            }
51760b57cec5SDimitry Andric                            ++__i;
51770b57cec5SDimitry Andric                        }
51780b57cec5SDimitry Andric                    }
51790b57cec5SDimitry Andric                    // [__first, __i) == *__first and *__first < [__j, __last) and __j == __last - 1
51800b57cec5SDimitry Andric                    if (__i == __j)
51810b57cec5SDimitry Andric                        return;
51820b57cec5SDimitry Andric                    while (true)
51830b57cec5SDimitry Andric                    {
51840b57cec5SDimitry Andric                        while (!__comp(*__first, *__i))
51850b57cec5SDimitry Andric                            ++__i;
51860b57cec5SDimitry Andric                        while (__comp(*__first, *--__j))
51870b57cec5SDimitry Andric                            ;
51880b57cec5SDimitry Andric                        if (__i >= __j)
51890b57cec5SDimitry Andric                            break;
51900b57cec5SDimitry Andric                        swap(*__i, *__j);
51910b57cec5SDimitry Andric                        ++__n_swaps;
51920b57cec5SDimitry Andric                        ++__i;
51930b57cec5SDimitry Andric                    }
51940b57cec5SDimitry Andric                    // [__first, __i) == *__first and *__first < [__i, __last)
51950b57cec5SDimitry Andric                    // The first part is sorted,
51960b57cec5SDimitry Andric                    if (__nth < __i)
51970b57cec5SDimitry Andric                        return;
51980b57cec5SDimitry Andric                    // __nth_element the secod part
51990b57cec5SDimitry Andric                    // __nth_element<_Compare>(__i, __nth, __last, __comp);
52000b57cec5SDimitry Andric                    __first = __i;
52010b57cec5SDimitry Andric                    goto __restart;
52020b57cec5SDimitry Andric                }
52030b57cec5SDimitry Andric                if (__comp(*__j, *__m))
52040b57cec5SDimitry Andric                {
52050b57cec5SDimitry Andric                    swap(*__i, *__j);
52060b57cec5SDimitry Andric                    ++__n_swaps;
52070b57cec5SDimitry Andric                    break;  // found guard for downward moving __j, now use unguarded partition
52080b57cec5SDimitry Andric                }
52090b57cec5SDimitry Andric            }
52100b57cec5SDimitry Andric        }
52110b57cec5SDimitry Andric        ++__i;
52120b57cec5SDimitry Andric        // j points beyond range to be tested, *__lm1 is known to be <= *__m
52130b57cec5SDimitry Andric        // if not yet partitioned...
52140b57cec5SDimitry Andric        if (__i < __j)
52150b57cec5SDimitry Andric        {
52160b57cec5SDimitry Andric            // known that *(__i - 1) < *__m
52170b57cec5SDimitry Andric            while (true)
52180b57cec5SDimitry Andric            {
52190b57cec5SDimitry Andric                // __m still guards upward moving __i
52200b57cec5SDimitry Andric                while (__comp(*__i, *__m))
52210b57cec5SDimitry Andric                    ++__i;
52220b57cec5SDimitry Andric                // It is now known that a guard exists for downward moving __j
52230b57cec5SDimitry Andric                while (!__comp(*--__j, *__m))
52240b57cec5SDimitry Andric                    ;
52250b57cec5SDimitry Andric                if (__i >= __j)
52260b57cec5SDimitry Andric                    break;
52270b57cec5SDimitry Andric                swap(*__i, *__j);
52280b57cec5SDimitry Andric                ++__n_swaps;
52290b57cec5SDimitry Andric                // It is known that __m != __j
52300b57cec5SDimitry Andric                // If __m just moved, follow it
52310b57cec5SDimitry Andric                if (__m == __i)
52320b57cec5SDimitry Andric                    __m = __j;
52330b57cec5SDimitry Andric                ++__i;
52340b57cec5SDimitry Andric            }
52350b57cec5SDimitry Andric        }
52360b57cec5SDimitry Andric        // [__first, __i) < *__m and *__m <= [__i, __last)
52370b57cec5SDimitry Andric        if (__i != __m && __comp(*__m, *__i))
52380b57cec5SDimitry Andric        {
52390b57cec5SDimitry Andric            swap(*__i, *__m);
52400b57cec5SDimitry Andric            ++__n_swaps;
52410b57cec5SDimitry Andric        }
52420b57cec5SDimitry Andric        // [__first, __i) < *__i and *__i <= [__i+1, __last)
52430b57cec5SDimitry Andric        if (__nth == __i)
52440b57cec5SDimitry Andric            return;
52450b57cec5SDimitry Andric        if (__n_swaps == 0)
52460b57cec5SDimitry Andric        {
52470b57cec5SDimitry Andric            // We were given a perfectly partitioned sequence.  Coincidence?
52480b57cec5SDimitry Andric            if (__nth < __i)
52490b57cec5SDimitry Andric            {
52500b57cec5SDimitry Andric                // Check for [__first, __i) already sorted
52510b57cec5SDimitry Andric                __j = __m = __first;
52520b57cec5SDimitry Andric                while (++__j != __i)
52530b57cec5SDimitry Andric                {
52540b57cec5SDimitry Andric                    if (__comp(*__j, *__m))
52550b57cec5SDimitry Andric                        // not yet sorted, so sort
52560b57cec5SDimitry Andric                        goto not_sorted;
52570b57cec5SDimitry Andric                    __m = __j;
52580b57cec5SDimitry Andric                }
52590b57cec5SDimitry Andric                // [__first, __i) sorted
52600b57cec5SDimitry Andric                return;
52610b57cec5SDimitry Andric            }
52620b57cec5SDimitry Andric            else
52630b57cec5SDimitry Andric            {
52640b57cec5SDimitry Andric                // Check for [__i, __last) already sorted
52650b57cec5SDimitry Andric                __j = __m = __i;
52660b57cec5SDimitry Andric                while (++__j != __last)
52670b57cec5SDimitry Andric                {
52680b57cec5SDimitry Andric                    if (__comp(*__j, *__m))
52690b57cec5SDimitry Andric                        // not yet sorted, so sort
52700b57cec5SDimitry Andric                        goto not_sorted;
52710b57cec5SDimitry Andric                    __m = __j;
52720b57cec5SDimitry Andric                }
52730b57cec5SDimitry Andric                // [__i, __last) sorted
52740b57cec5SDimitry Andric                return;
52750b57cec5SDimitry Andric            }
52760b57cec5SDimitry Andric        }
52770b57cec5SDimitry Andricnot_sorted:
52780b57cec5SDimitry Andric        // __nth_element on range containing __nth
52790b57cec5SDimitry Andric        if (__nth < __i)
52800b57cec5SDimitry Andric        {
52810b57cec5SDimitry Andric            // __nth_element<_Compare>(__first, __nth, __i, __comp);
52820b57cec5SDimitry Andric            __last = __i;
52830b57cec5SDimitry Andric        }
52840b57cec5SDimitry Andric        else
52850b57cec5SDimitry Andric        {
52860b57cec5SDimitry Andric            // __nth_element<_Compare>(__i+1, __nth, __last, __comp);
52870b57cec5SDimitry Andric            __first = ++__i;
52880b57cec5SDimitry Andric        }
52890b57cec5SDimitry Andric    }
52900b57cec5SDimitry Andric}
52910b57cec5SDimitry Andric
52920b57cec5SDimitry Andrictemplate <class _RandomAccessIterator, class _Compare>
52930b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
52940b57cec5SDimitry Andricvoid
52950b57cec5SDimitry Andricnth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth, _RandomAccessIterator __last, _Compare __comp)
52960b57cec5SDimitry Andric{
52970b57cec5SDimitry Andric    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
52980b57cec5SDimitry Andric    __nth_element<_Comp_ref>(__first, __nth, __last, __comp);
52990b57cec5SDimitry Andric}
53000b57cec5SDimitry Andric
53010b57cec5SDimitry Andrictemplate <class _RandomAccessIterator>
53020b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
53030b57cec5SDimitry Andricvoid
53040b57cec5SDimitry Andricnth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth, _RandomAccessIterator __last)
53050b57cec5SDimitry Andric{
53060b57cec5SDimitry Andric    _VSTD::nth_element(__first, __nth, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
53070b57cec5SDimitry Andric}
53080b57cec5SDimitry Andric
53090b57cec5SDimitry Andric// includes
53100b57cec5SDimitry Andric
53110b57cec5SDimitry Andrictemplate <class _Compare, class _InputIterator1, class _InputIterator2>
53120b57cec5SDimitry Andric_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
53130b57cec5SDimitry Andric__includes(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2,
53140b57cec5SDimitry Andric           _Compare __comp)
53150b57cec5SDimitry Andric{
53160b57cec5SDimitry Andric    for (; __first2 != __last2; ++__first1)
53170b57cec5SDimitry Andric    {
53180b57cec5SDimitry Andric        if (__first1 == __last1 || __comp(*__first2, *__first1))
53190b57cec5SDimitry Andric            return false;
53200b57cec5SDimitry Andric        if (!__comp(*__first1, *__first2))
53210b57cec5SDimitry Andric            ++__first2;
53220b57cec5SDimitry Andric    }
53230b57cec5SDimitry Andric    return true;
53240b57cec5SDimitry Andric}
53250b57cec5SDimitry Andric
53260b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2, class _Compare>
53270b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
53280b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
53290b57cec5SDimitry Andricbool
53300b57cec5SDimitry Andricincludes(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2,
53310b57cec5SDimitry Andric         _Compare __comp)
53320b57cec5SDimitry Andric{
53330b57cec5SDimitry Andric    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
53340b57cec5SDimitry Andric    return __includes<_Comp_ref>(__first1, __last1, __first2, __last2, __comp);
53350b57cec5SDimitry Andric}
53360b57cec5SDimitry Andric
53370b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2>
53380b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
53390b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
53400b57cec5SDimitry Andricbool
53410b57cec5SDimitry Andricincludes(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2)
53420b57cec5SDimitry Andric{
53430b57cec5SDimitry Andric    return _VSTD::includes(__first1, __last1, __first2, __last2,
53440b57cec5SDimitry Andric                          __less<typename iterator_traits<_InputIterator1>::value_type,
53450b57cec5SDimitry Andric                                 typename iterator_traits<_InputIterator2>::value_type>());
53460b57cec5SDimitry Andric}
53470b57cec5SDimitry Andric
53480b57cec5SDimitry Andric// set_union
53490b57cec5SDimitry Andric
53500b57cec5SDimitry Andrictemplate <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
53510b57cec5SDimitry Andric_OutputIterator
53520b57cec5SDimitry Andric__set_union(_InputIterator1 __first1, _InputIterator1 __last1,
53530b57cec5SDimitry Andric            _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
53540b57cec5SDimitry Andric{
53550b57cec5SDimitry Andric    for (; __first1 != __last1; ++__result)
53560b57cec5SDimitry Andric    {
53570b57cec5SDimitry Andric        if (__first2 == __last2)
53580b57cec5SDimitry Andric            return _VSTD::copy(__first1, __last1, __result);
53590b57cec5SDimitry Andric        if (__comp(*__first2, *__first1))
53600b57cec5SDimitry Andric        {
53610b57cec5SDimitry Andric            *__result = *__first2;
53620b57cec5SDimitry Andric            ++__first2;
53630b57cec5SDimitry Andric        }
53640b57cec5SDimitry Andric        else
53650b57cec5SDimitry Andric        {
53660b57cec5SDimitry Andric            if (!__comp(*__first1, *__first2))
53670b57cec5SDimitry Andric                ++__first2;
53680b57cec5SDimitry Andric            *__result = *__first1;
53690b57cec5SDimitry Andric            ++__first1;
53700b57cec5SDimitry Andric        }
53710b57cec5SDimitry Andric    }
53720b57cec5SDimitry Andric    return _VSTD::copy(__first2, __last2, __result);
53730b57cec5SDimitry Andric}
53740b57cec5SDimitry Andric
53750b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
53760b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
53770b57cec5SDimitry Andric_OutputIterator
53780b57cec5SDimitry Andricset_union(_InputIterator1 __first1, _InputIterator1 __last1,
53790b57cec5SDimitry Andric          _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
53800b57cec5SDimitry Andric{
53810b57cec5SDimitry Andric    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
53820b57cec5SDimitry Andric    return __set_union<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
53830b57cec5SDimitry Andric}
53840b57cec5SDimitry Andric
53850b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator>
53860b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
53870b57cec5SDimitry Andric_OutputIterator
53880b57cec5SDimitry Andricset_union(_InputIterator1 __first1, _InputIterator1 __last1,
53890b57cec5SDimitry Andric          _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
53900b57cec5SDimitry Andric{
53910b57cec5SDimitry Andric    return _VSTD::set_union(__first1, __last1, __first2, __last2, __result,
53920b57cec5SDimitry Andric                          __less<typename iterator_traits<_InputIterator1>::value_type,
53930b57cec5SDimitry Andric                                 typename iterator_traits<_InputIterator2>::value_type>());
53940b57cec5SDimitry Andric}
53950b57cec5SDimitry Andric
53960b57cec5SDimitry Andric// set_intersection
53970b57cec5SDimitry Andric
53980b57cec5SDimitry Andrictemplate <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
53990b57cec5SDimitry Andric_LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
54000b57cec5SDimitry Andric__set_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
54010b57cec5SDimitry Andric                   _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
54020b57cec5SDimitry Andric{
54030b57cec5SDimitry Andric    while (__first1 != __last1 && __first2 != __last2)
54040b57cec5SDimitry Andric    {
54050b57cec5SDimitry Andric        if (__comp(*__first1, *__first2))
54060b57cec5SDimitry Andric            ++__first1;
54070b57cec5SDimitry Andric        else
54080b57cec5SDimitry Andric        {
54090b57cec5SDimitry Andric            if (!__comp(*__first2, *__first1))
54100b57cec5SDimitry Andric            {
54110b57cec5SDimitry Andric                *__result = *__first1;
54120b57cec5SDimitry Andric                ++__result;
54130b57cec5SDimitry Andric                ++__first1;
54140b57cec5SDimitry Andric            }
54150b57cec5SDimitry Andric            ++__first2;
54160b57cec5SDimitry Andric        }
54170b57cec5SDimitry Andric    }
54180b57cec5SDimitry Andric    return __result;
54190b57cec5SDimitry Andric}
54200b57cec5SDimitry Andric
54210b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
54220b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
54230b57cec5SDimitry Andric_OutputIterator
54240b57cec5SDimitry Andricset_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
54250b57cec5SDimitry Andric                 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
54260b57cec5SDimitry Andric{
54270b57cec5SDimitry Andric    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
54280b57cec5SDimitry Andric    return __set_intersection<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
54290b57cec5SDimitry Andric}
54300b57cec5SDimitry Andric
54310b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator>
54320b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
54330b57cec5SDimitry Andric_OutputIterator
54340b57cec5SDimitry Andricset_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
54350b57cec5SDimitry Andric                 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
54360b57cec5SDimitry Andric{
54370b57cec5SDimitry Andric    return _VSTD::set_intersection(__first1, __last1, __first2, __last2, __result,
54380b57cec5SDimitry Andric                                  __less<typename iterator_traits<_InputIterator1>::value_type,
54390b57cec5SDimitry Andric                                         typename iterator_traits<_InputIterator2>::value_type>());
54400b57cec5SDimitry Andric}
54410b57cec5SDimitry Andric
54420b57cec5SDimitry Andric// set_difference
54430b57cec5SDimitry Andric
54440b57cec5SDimitry Andrictemplate <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
54450b57cec5SDimitry Andric_OutputIterator
54460b57cec5SDimitry Andric__set_difference(_InputIterator1 __first1, _InputIterator1 __last1,
54470b57cec5SDimitry Andric                 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
54480b57cec5SDimitry Andric{
54490b57cec5SDimitry Andric    while (__first1 != __last1)
54500b57cec5SDimitry Andric    {
54510b57cec5SDimitry Andric        if (__first2 == __last2)
54520b57cec5SDimitry Andric            return _VSTD::copy(__first1, __last1, __result);
54530b57cec5SDimitry Andric        if (__comp(*__first1, *__first2))
54540b57cec5SDimitry Andric        {
54550b57cec5SDimitry Andric            *__result = *__first1;
54560b57cec5SDimitry Andric            ++__result;
54570b57cec5SDimitry Andric            ++__first1;
54580b57cec5SDimitry Andric        }
54590b57cec5SDimitry Andric        else
54600b57cec5SDimitry Andric        {
54610b57cec5SDimitry Andric            if (!__comp(*__first2, *__first1))
54620b57cec5SDimitry Andric                ++__first1;
54630b57cec5SDimitry Andric            ++__first2;
54640b57cec5SDimitry Andric        }
54650b57cec5SDimitry Andric    }
54660b57cec5SDimitry Andric    return __result;
54670b57cec5SDimitry Andric}
54680b57cec5SDimitry Andric
54690b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
54700b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
54710b57cec5SDimitry Andric_OutputIterator
54720b57cec5SDimitry Andricset_difference(_InputIterator1 __first1, _InputIterator1 __last1,
54730b57cec5SDimitry Andric               _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
54740b57cec5SDimitry Andric{
54750b57cec5SDimitry Andric    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
54760b57cec5SDimitry Andric    return __set_difference<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
54770b57cec5SDimitry Andric}
54780b57cec5SDimitry Andric
54790b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator>
54800b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
54810b57cec5SDimitry Andric_OutputIterator
54820b57cec5SDimitry Andricset_difference(_InputIterator1 __first1, _InputIterator1 __last1,
54830b57cec5SDimitry Andric               _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
54840b57cec5SDimitry Andric{
54850b57cec5SDimitry Andric    return _VSTD::set_difference(__first1, __last1, __first2, __last2, __result,
54860b57cec5SDimitry Andric                                __less<typename iterator_traits<_InputIterator1>::value_type,
54870b57cec5SDimitry Andric                                       typename iterator_traits<_InputIterator2>::value_type>());
54880b57cec5SDimitry Andric}
54890b57cec5SDimitry Andric
54900b57cec5SDimitry Andric// set_symmetric_difference
54910b57cec5SDimitry Andric
54920b57cec5SDimitry Andrictemplate <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
54930b57cec5SDimitry Andric_OutputIterator
54940b57cec5SDimitry Andric__set_symmetric_difference(_InputIterator1 __first1, _InputIterator1 __last1,
54950b57cec5SDimitry Andric                           _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
54960b57cec5SDimitry Andric{
54970b57cec5SDimitry Andric    while (__first1 != __last1)
54980b57cec5SDimitry Andric    {
54990b57cec5SDimitry Andric        if (__first2 == __last2)
55000b57cec5SDimitry Andric            return _VSTD::copy(__first1, __last1, __result);
55010b57cec5SDimitry Andric        if (__comp(*__first1, *__first2))
55020b57cec5SDimitry Andric        {
55030b57cec5SDimitry Andric            *__result = *__first1;
55040b57cec5SDimitry Andric            ++__result;
55050b57cec5SDimitry Andric            ++__first1;
55060b57cec5SDimitry Andric        }
55070b57cec5SDimitry Andric        else
55080b57cec5SDimitry Andric        {
55090b57cec5SDimitry Andric            if (__comp(*__first2, *__first1))
55100b57cec5SDimitry Andric            {
55110b57cec5SDimitry Andric                *__result = *__first2;
55120b57cec5SDimitry Andric                ++__result;
55130b57cec5SDimitry Andric            }
55140b57cec5SDimitry Andric            else
55150b57cec5SDimitry Andric                ++__first1;
55160b57cec5SDimitry Andric            ++__first2;
55170b57cec5SDimitry Andric        }
55180b57cec5SDimitry Andric    }
55190b57cec5SDimitry Andric    return _VSTD::copy(__first2, __last2, __result);
55200b57cec5SDimitry Andric}
55210b57cec5SDimitry Andric
55220b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
55230b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
55240b57cec5SDimitry Andric_OutputIterator
55250b57cec5SDimitry Andricset_symmetric_difference(_InputIterator1 __first1, _InputIterator1 __last1,
55260b57cec5SDimitry Andric                         _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
55270b57cec5SDimitry Andric{
55280b57cec5SDimitry Andric    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
55290b57cec5SDimitry Andric    return __set_symmetric_difference<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
55300b57cec5SDimitry Andric}
55310b57cec5SDimitry Andric
55320b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator>
55330b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
55340b57cec5SDimitry Andric_OutputIterator
55350b57cec5SDimitry Andricset_symmetric_difference(_InputIterator1 __first1, _InputIterator1 __last1,
55360b57cec5SDimitry Andric                         _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
55370b57cec5SDimitry Andric{
55380b57cec5SDimitry Andric    return _VSTD::set_symmetric_difference(__first1, __last1, __first2, __last2, __result,
55390b57cec5SDimitry Andric                                          __less<typename iterator_traits<_InputIterator1>::value_type,
55400b57cec5SDimitry Andric                                                 typename iterator_traits<_InputIterator2>::value_type>());
55410b57cec5SDimitry Andric}
55420b57cec5SDimitry Andric
55430b57cec5SDimitry Andric// lexicographical_compare
55440b57cec5SDimitry Andric
55450b57cec5SDimitry Andrictemplate <class _Compare, class _InputIterator1, class _InputIterator2>
55460b57cec5SDimitry Andric_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
55470b57cec5SDimitry Andric__lexicographical_compare(_InputIterator1 __first1, _InputIterator1 __last1,
55480b57cec5SDimitry Andric                          _InputIterator2 __first2, _InputIterator2 __last2, _Compare __comp)
55490b57cec5SDimitry Andric{
55500b57cec5SDimitry Andric    for (; __first2 != __last2; ++__first1, (void) ++__first2)
55510b57cec5SDimitry Andric    {
55520b57cec5SDimitry Andric        if (__first1 == __last1 || __comp(*__first1, *__first2))
55530b57cec5SDimitry Andric            return true;
55540b57cec5SDimitry Andric        if (__comp(*__first2, *__first1))
55550b57cec5SDimitry Andric            return false;
55560b57cec5SDimitry Andric    }
55570b57cec5SDimitry Andric    return false;
55580b57cec5SDimitry Andric}
55590b57cec5SDimitry Andric
55600b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2, class _Compare>
55610b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
55620b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
55630b57cec5SDimitry Andricbool
55640b57cec5SDimitry Andriclexicographical_compare(_InputIterator1 __first1, _InputIterator1 __last1,
55650b57cec5SDimitry Andric                        _InputIterator2 __first2, _InputIterator2 __last2, _Compare __comp)
55660b57cec5SDimitry Andric{
55670b57cec5SDimitry Andric    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
55680b57cec5SDimitry Andric    return __lexicographical_compare<_Comp_ref>(__first1, __last1, __first2, __last2, __comp);
55690b57cec5SDimitry Andric}
55700b57cec5SDimitry Andric
55710b57cec5SDimitry Andrictemplate <class _InputIterator1, class _InputIterator2>
55720b57cec5SDimitry Andric_LIBCPP_NODISCARD_EXT inline
55730b57cec5SDimitry Andric_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
55740b57cec5SDimitry Andricbool
55750b57cec5SDimitry Andriclexicographical_compare(_InputIterator1 __first1, _InputIterator1 __last1,
55760b57cec5SDimitry Andric                        _InputIterator2 __first2, _InputIterator2 __last2)
55770b57cec5SDimitry Andric{
55780b57cec5SDimitry Andric    return _VSTD::lexicographical_compare(__first1, __last1, __first2, __last2,
55790b57cec5SDimitry Andric                                         __less<typename iterator_traits<_InputIterator1>::value_type,
55800b57cec5SDimitry Andric                                                typename iterator_traits<_InputIterator2>::value_type>());
55810b57cec5SDimitry Andric}
55820b57cec5SDimitry Andric
55830b57cec5SDimitry Andric// next_permutation
55840b57cec5SDimitry Andric
55850b57cec5SDimitry Andrictemplate <class _Compare, class _BidirectionalIterator>
55860b57cec5SDimitry Andricbool
55870b57cec5SDimitry Andric__next_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
55880b57cec5SDimitry Andric{
55890b57cec5SDimitry Andric    _BidirectionalIterator __i = __last;
55900b57cec5SDimitry Andric    if (__first == __last || __first == --__i)
55910b57cec5SDimitry Andric        return false;
55920b57cec5SDimitry Andric    while (true)
55930b57cec5SDimitry Andric    {
55940b57cec5SDimitry Andric        _BidirectionalIterator __ip1 = __i;
55950b57cec5SDimitry Andric        if (__comp(*--__i, *__ip1))
55960b57cec5SDimitry Andric        {
55970b57cec5SDimitry Andric            _BidirectionalIterator __j = __last;
55980b57cec5SDimitry Andric            while (!__comp(*__i, *--__j))
55990b57cec5SDimitry Andric                ;
56000b57cec5SDimitry Andric            swap(*__i, *__j);
56010b57cec5SDimitry Andric            _VSTD::reverse(__ip1, __last);
56020b57cec5SDimitry Andric            return true;
56030b57cec5SDimitry Andric        }
56040b57cec5SDimitry Andric        if (__i == __first)
56050b57cec5SDimitry Andric        {
56060b57cec5SDimitry Andric            _VSTD::reverse(__first, __last);
56070b57cec5SDimitry Andric            return false;
56080b57cec5SDimitry Andric        }
56090b57cec5SDimitry Andric    }
56100b57cec5SDimitry Andric}
56110b57cec5SDimitry Andric
56120b57cec5SDimitry Andrictemplate <class _BidirectionalIterator, class _Compare>
56130b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
56140b57cec5SDimitry Andricbool
56150b57cec5SDimitry Andricnext_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
56160b57cec5SDimitry Andric{
56170b57cec5SDimitry Andric    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
56180b57cec5SDimitry Andric    return __next_permutation<_Comp_ref>(__first, __last, __comp);
56190b57cec5SDimitry Andric}
56200b57cec5SDimitry Andric
56210b57cec5SDimitry Andrictemplate <class _BidirectionalIterator>
56220b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
56230b57cec5SDimitry Andricbool
56240b57cec5SDimitry Andricnext_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last)
56250b57cec5SDimitry Andric{
56260b57cec5SDimitry Andric    return _VSTD::next_permutation(__first, __last,
56270b57cec5SDimitry Andric                                  __less<typename iterator_traits<_BidirectionalIterator>::value_type>());
56280b57cec5SDimitry Andric}
56290b57cec5SDimitry Andric
56300b57cec5SDimitry Andric// prev_permutation
56310b57cec5SDimitry Andric
56320b57cec5SDimitry Andrictemplate <class _Compare, class _BidirectionalIterator>
56330b57cec5SDimitry Andricbool
56340b57cec5SDimitry Andric__prev_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
56350b57cec5SDimitry Andric{
56360b57cec5SDimitry Andric    _BidirectionalIterator __i = __last;
56370b57cec5SDimitry Andric    if (__first == __last || __first == --__i)
56380b57cec5SDimitry Andric        return false;
56390b57cec5SDimitry Andric    while (true)
56400b57cec5SDimitry Andric    {
56410b57cec5SDimitry Andric        _BidirectionalIterator __ip1 = __i;
56420b57cec5SDimitry Andric        if (__comp(*__ip1, *--__i))
56430b57cec5SDimitry Andric        {
56440b57cec5SDimitry Andric            _BidirectionalIterator __j = __last;
56450b57cec5SDimitry Andric            while (!__comp(*--__j, *__i))
56460b57cec5SDimitry Andric                ;
56470b57cec5SDimitry Andric            swap(*__i, *__j);
56480b57cec5SDimitry Andric            _VSTD::reverse(__ip1, __last);
56490b57cec5SDimitry Andric            return true;
56500b57cec5SDimitry Andric        }
56510b57cec5SDimitry Andric        if (__i == __first)
56520b57cec5SDimitry Andric        {
56530b57cec5SDimitry Andric            _VSTD::reverse(__first, __last);
56540b57cec5SDimitry Andric            return false;
56550b57cec5SDimitry Andric        }
56560b57cec5SDimitry Andric    }
56570b57cec5SDimitry Andric}
56580b57cec5SDimitry Andric
56590b57cec5SDimitry Andrictemplate <class _BidirectionalIterator, class _Compare>
56600b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
56610b57cec5SDimitry Andricbool
56620b57cec5SDimitry Andricprev_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
56630b57cec5SDimitry Andric{
56640b57cec5SDimitry Andric    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
56650b57cec5SDimitry Andric    return __prev_permutation<_Comp_ref>(__first, __last, __comp);
56660b57cec5SDimitry Andric}
56670b57cec5SDimitry Andric
56680b57cec5SDimitry Andrictemplate <class _BidirectionalIterator>
56690b57cec5SDimitry Andricinline _LIBCPP_INLINE_VISIBILITY
56700b57cec5SDimitry Andricbool
56710b57cec5SDimitry Andricprev_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last)
56720b57cec5SDimitry Andric{
56730b57cec5SDimitry Andric    return _VSTD::prev_permutation(__first, __last,
56740b57cec5SDimitry Andric                                  __less<typename iterator_traits<_BidirectionalIterator>::value_type>());
56750b57cec5SDimitry Andric}
56760b57cec5SDimitry Andric
56770b57cec5SDimitry Andric_LIBCPP_END_NAMESPACE_STD
56780b57cec5SDimitry Andric
56790b57cec5SDimitry Andric_LIBCPP_POP_MACROS
56800b57cec5SDimitry Andric
5681*e40139ffSDimitry Andric#if defined(_LIBCPP_HAS_PARALLEL_ALGORITHMS) && _LIBCPP_STD_VER >= 17
5682*e40139ffSDimitry Andric#   include <__pstl_algorithm>
5683*e40139ffSDimitry Andric#endif
5684*e40139ffSDimitry Andric
56850b57cec5SDimitry Andric#endif  // _LIBCPP_ALGORITHM
5686