xref: /freebsd/contrib/llvm-project/libcxx/include/unordered_set (revision 4824e7fd18a1223177218d4aec1b3c6c5c4a444e)
1// -*- C++ -*-
2//===----------------------------------------------------------------------===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef _LIBCPP_UNORDERED_SET
11#define _LIBCPP_UNORDERED_SET
12
13/*
14
15    unordered_set synopsis
16
17#include <initializer_list>
18
19namespace std
20{
21
22template <class Value, class Hash = hash<Value>, class Pred = equal_to<Value>,
23          class Alloc = allocator<Value>>
24class unordered_set
25{
26public:
27    // types
28    typedef Value                                                      key_type;
29    typedef key_type                                                   value_type;
30    typedef Hash                                                       hasher;
31    typedef Pred                                                       key_equal;
32    typedef Alloc                                                      allocator_type;
33    typedef value_type&                                                reference;
34    typedef const value_type&                                          const_reference;
35    typedef typename allocator_traits<allocator_type>::pointer         pointer;
36    typedef typename allocator_traits<allocator_type>::const_pointer   const_pointer;
37    typedef typename allocator_traits<allocator_type>::size_type       size_type;
38    typedef typename allocator_traits<allocator_type>::difference_type difference_type;
39
40    typedef /unspecified/ iterator;
41    typedef /unspecified/ const_iterator;
42    typedef /unspecified/ local_iterator;
43    typedef /unspecified/ const_local_iterator;
44
45    typedef unspecified node_type unspecified;                            // C++17
46    typedef INSERT_RETURN_TYPE<iterator, node_type> insert_return_type;   // C++17
47
48    unordered_set()
49        noexcept(
50            is_nothrow_default_constructible<hasher>::value &&
51            is_nothrow_default_constructible<key_equal>::value &&
52            is_nothrow_default_constructible<allocator_type>::value);
53    explicit unordered_set(size_type n, const hasher& hf = hasher(),
54                           const key_equal& eql = key_equal(),
55                           const allocator_type& a = allocator_type());
56    template <class InputIterator>
57        unordered_set(InputIterator f, InputIterator l,
58                      size_type n = 0, const hasher& hf = hasher(),
59                      const key_equal& eql = key_equal(),
60                      const allocator_type& a = allocator_type());
61    explicit unordered_set(const allocator_type&);
62    unordered_set(const unordered_set&);
63    unordered_set(const unordered_set&, const Allocator&);
64    unordered_set(unordered_set&&)
65        noexcept(
66            is_nothrow_move_constructible<hasher>::value &&
67            is_nothrow_move_constructible<key_equal>::value &&
68            is_nothrow_move_constructible<allocator_type>::value);
69    unordered_set(unordered_set&&, const Allocator&);
70    unordered_set(initializer_list<value_type>, size_type n = 0,
71                  const hasher& hf = hasher(), const key_equal& eql = key_equal(),
72                  const allocator_type& a = allocator_type());
73    unordered_set(size_type n, const allocator_type& a); // C++14
74    unordered_set(size_type n, const hasher& hf, const allocator_type& a); // C++14
75    template <class InputIterator>
76      unordered_set(InputIterator f, InputIterator l, size_type n, const allocator_type& a); // C++14
77    template <class InputIterator>
78      unordered_set(InputIterator f, InputIterator l, size_type n,
79                    const hasher& hf,  const allocator_type& a); // C++14
80    unordered_set(initializer_list<value_type> il, size_type n, const allocator_type& a); // C++14
81    unordered_set(initializer_list<value_type> il, size_type n,
82                  const hasher& hf,  const allocator_type& a); // C++14
83    ~unordered_set();
84    unordered_set& operator=(const unordered_set&);
85    unordered_set& operator=(unordered_set&&)
86        noexcept(
87            allocator_type::propagate_on_container_move_assignment::value &&
88            is_nothrow_move_assignable<allocator_type>::value &&
89            is_nothrow_move_assignable<hasher>::value &&
90            is_nothrow_move_assignable<key_equal>::value);
91    unordered_set& operator=(initializer_list<value_type>);
92
93    allocator_type get_allocator() const noexcept;
94
95    bool      empty() const noexcept;
96    size_type size() const noexcept;
97    size_type max_size() const noexcept;
98
99    iterator       begin() noexcept;
100    iterator       end() noexcept;
101    const_iterator begin()  const noexcept;
102    const_iterator end()    const noexcept;
103    const_iterator cbegin() const noexcept;
104    const_iterator cend()   const noexcept;
105
106    template <class... Args>
107        pair<iterator, bool> emplace(Args&&... args);
108    template <class... Args>
109        iterator emplace_hint(const_iterator position, Args&&... args);
110    pair<iterator, bool> insert(const value_type& obj);
111    pair<iterator, bool> insert(value_type&& obj);
112    iterator insert(const_iterator hint, const value_type& obj);
113    iterator insert(const_iterator hint, value_type&& obj);
114    template <class InputIterator>
115        void insert(InputIterator first, InputIterator last);
116    void insert(initializer_list<value_type>);
117
118    node_type extract(const_iterator position);                       // C++17
119    node_type extract(const key_type& x);                             // C++17
120    insert_return_type insert(node_type&& nh);                        // C++17
121    iterator           insert(const_iterator hint, node_type&& nh);   // C++17
122
123    iterator erase(const_iterator position);
124    iterator erase(iterator position);  // C++14
125    size_type erase(const key_type& k);
126    iterator erase(const_iterator first, const_iterator last);
127    void clear() noexcept;
128
129    template<class H2, class P2>
130      void merge(unordered_set<Key, H2, P2, Allocator>& source);         // C++17
131    template<class H2, class P2>
132      void merge(unordered_set<Key, H2, P2, Allocator>&& source);        // C++17
133    template<class H2, class P2>
134      void merge(unordered_multiset<Key, H2, P2, Allocator>& source);    // C++17
135    template<class H2, class P2>
136      void merge(unordered_multiset<Key, H2, P2, Allocator>&& source);   // C++17
137
138    void swap(unordered_set&)
139       noexcept(allocator_traits<Allocator>::is_always_equal::value &&
140                 noexcept(swap(declval<hasher&>(), declval<hasher&>())) &&
141                 noexcept(swap(declval<key_equal&>(), declval<key_equal&>()))); // C++17
142
143    hasher hash_function() const;
144    key_equal key_eq() const;
145
146    iterator       find(const key_type& k);
147    const_iterator find(const key_type& k) const;
148    template<typename K>
149        iterator find(const K& x);              // C++20
150    template<typename K>
151        const_iterator find(const K& x) const;  // C++20
152    size_type count(const key_type& k) const;
153    template<typename K>
154        size_type count(const K& k) const; // C++20
155    bool contains(const key_type& k) const; // C++20
156    template<typename K>
157        bool contains(const K& k) const; // C++20
158    pair<iterator, iterator>             equal_range(const key_type& k);
159    pair<const_iterator, const_iterator> equal_range(const key_type& k) const;
160    template<typename K>
161        pair<iterator, iterator>             equal_range(const K& k); // C++20
162    template<typename K>
163        pair<const_iterator, const_iterator> equal_range(const K& k) const; // C++20
164
165    size_type bucket_count() const noexcept;
166    size_type max_bucket_count() const noexcept;
167
168    size_type bucket_size(size_type n) const;
169    size_type bucket(const key_type& k) const;
170
171    local_iterator       begin(size_type n);
172    local_iterator       end(size_type n);
173    const_local_iterator begin(size_type n) const;
174    const_local_iterator end(size_type n) const;
175    const_local_iterator cbegin(size_type n) const;
176    const_local_iterator cend(size_type n) const;
177
178    float load_factor() const noexcept;
179    float max_load_factor() const noexcept;
180    void max_load_factor(float z);
181    void rehash(size_type n);
182    void reserve(size_type n);
183};
184
185template<class InputIterator,
186    class Hash = hash<typename iterator_traits<InputIterator>::value_type>,
187    class Pred = equal_to<typename iterator_traits<InputIterator>::value_type>,
188    class Allocator = allocator<typename iterator_traits<InputIterator>::value_type>>
189unordered_set(InputIterator, InputIterator, typename see below::size_type = see below,
190    Hash = Hash(), Pred = Pred(), Allocator = Allocator())
191  -> unordered_set<typename iterator_traits<InputIterator>::value_type,
192        Hash, Pred, Allocator>; // C++17
193
194template<class T, class Hash = hash<T>,
195          class Pred = equal_to<T>, class Allocator = allocator<T>>
196unordered_set(initializer_list<T>, typename see below::size_type = see below,
197    Hash = Hash(), Pred = Pred(), Allocator = Allocator())
198  -> unordered_set<T, Hash, Pred, Allocator>; // C++17
199
200template<class InputIterator,  class Allocator>
201unordered_set(InputIterator, InputIterator, typename see below::size_type, Allocator)
202  -> unordered_set<typename iterator_traits<InputIterator>::value_type,
203        hash<typename iterator_traits<InputIterator>::value_type>,
204        equal_to<typename iterator_traits<InputIterator>::value_type>,
205        Allocator>; // C++17
206
207template<class InputIterator, class Hash, class Allocator>
208unordered_set(InputIterator, InputIterator, typename see below::size_type,
209    Hash, Allocator)
210  -> unordered_set<typename iterator_traits<InputIterator>::value_type, Hash,
211        equal_to<typename iterator_traits<InputIterator>::value_type>,
212        Allocator>; // C++17
213
214template<class T, class Allocator>
215unordered_set(initializer_list<T>, typename see below::size_type, Allocator)
216  -> unordered_set<T, hash<T>, equal_to<T>, Allocator>; // C++17
217
218template<class T, class Hash, class Allocator>
219unordered_set(initializer_list<T>, typename see below::size_type, Hash, Allocator)
220  -> unordered_set<T, Hash, equal_to<T>, Allocator>; // C++17
221
222template <class Value, class Hash, class Pred, class Alloc>
223    void swap(unordered_set<Value, Hash, Pred, Alloc>& x,
224              unordered_set<Value, Hash, Pred, Alloc>& y)
225              noexcept(noexcept(x.swap(y)));
226
227template <class Value, class Hash, class Pred, class Alloc>
228    bool
229    operator==(const unordered_set<Value, Hash, Pred, Alloc>& x,
230               const unordered_set<Value, Hash, Pred, Alloc>& y);
231
232template <class Value, class Hash, class Pred, class Alloc>
233    bool
234    operator!=(const unordered_set<Value, Hash, Pred, Alloc>& x,
235               const unordered_set<Value, Hash, Pred, Alloc>& y);
236
237template <class Value, class Hash = hash<Value>, class Pred = equal_to<Value>,
238          class Alloc = allocator<Value>>
239class unordered_multiset
240{
241public:
242    // types
243    typedef Value                                                      key_type;
244    typedef key_type                                                   value_type;
245    typedef Hash                                                       hasher;
246    typedef Pred                                                       key_equal;
247    typedef Alloc                                                      allocator_type;
248    typedef value_type&                                                reference;
249    typedef const value_type&                                          const_reference;
250    typedef typename allocator_traits<allocator_type>::pointer         pointer;
251    typedef typename allocator_traits<allocator_type>::const_pointer   const_pointer;
252    typedef typename allocator_traits<allocator_type>::size_type       size_type;
253    typedef typename allocator_traits<allocator_type>::difference_type difference_type;
254
255    typedef /unspecified/ iterator;
256    typedef /unspecified/ const_iterator;
257    typedef /unspecified/ local_iterator;
258    typedef /unspecified/ const_local_iterator;
259
260    typedef unspecified node_type unspecified;   // C++17
261
262    unordered_multiset()
263        noexcept(
264            is_nothrow_default_constructible<hasher>::value &&
265            is_nothrow_default_constructible<key_equal>::value &&
266            is_nothrow_default_constructible<allocator_type>::value);
267    explicit unordered_multiset(size_type n, const hasher& hf = hasher(),
268                           const key_equal& eql = key_equal(),
269                           const allocator_type& a = allocator_type());
270    template <class InputIterator>
271        unordered_multiset(InputIterator f, InputIterator l,
272                      size_type n = 0, const hasher& hf = hasher(),
273                      const key_equal& eql = key_equal(),
274                      const allocator_type& a = allocator_type());
275    explicit unordered_multiset(const allocator_type&);
276    unordered_multiset(const unordered_multiset&);
277    unordered_multiset(const unordered_multiset&, const Allocator&);
278    unordered_multiset(unordered_multiset&&)
279        noexcept(
280            is_nothrow_move_constructible<hasher>::value &&
281            is_nothrow_move_constructible<key_equal>::value &&
282            is_nothrow_move_constructible<allocator_type>::value);
283    unordered_multiset(unordered_multiset&&, const Allocator&);
284    unordered_multiset(initializer_list<value_type>, size_type n = /see below/,
285                  const hasher& hf = hasher(), const key_equal& eql = key_equal(),
286                  const allocator_type& a = allocator_type());
287    unordered_multiset(size_type n, const allocator_type& a); // C++14
288    unordered_multiset(size_type n, const hasher& hf, const allocator_type& a); // C++14
289    template <class InputIterator>
290      unordered_multiset(InputIterator f, InputIterator l, size_type n, const allocator_type& a); // C++14
291    template <class InputIterator>
292      unordered_multiset(InputIterator f, InputIterator l, size_type n,
293                         const hasher& hf, const allocator_type& a); // C++14
294    unordered_multiset(initializer_list<value_type> il, size_type n, const allocator_type& a); // C++14
295    unordered_multiset(initializer_list<value_type> il, size_type n,
296                       const hasher& hf,  const allocator_type& a); // C++14
297    ~unordered_multiset();
298    unordered_multiset& operator=(const unordered_multiset&);
299    unordered_multiset& operator=(unordered_multiset&&)
300        noexcept(
301            allocator_type::propagate_on_container_move_assignment::value &&
302            is_nothrow_move_assignable<allocator_type>::value &&
303            is_nothrow_move_assignable<hasher>::value &&
304            is_nothrow_move_assignable<key_equal>::value);
305    unordered_multiset& operator=(initializer_list<value_type>);
306
307    allocator_type get_allocator() const noexcept;
308
309    bool      empty() const noexcept;
310    size_type size() const noexcept;
311    size_type max_size() const noexcept;
312
313    iterator       begin() noexcept;
314    iterator       end() noexcept;
315    const_iterator begin()  const noexcept;
316    const_iterator end()    const noexcept;
317    const_iterator cbegin() const noexcept;
318    const_iterator cend()   const noexcept;
319
320    template <class... Args>
321        iterator emplace(Args&&... args);
322    template <class... Args>
323        iterator emplace_hint(const_iterator position, Args&&... args);
324    iterator insert(const value_type& obj);
325    iterator insert(value_type&& obj);
326    iterator insert(const_iterator hint, const value_type& obj);
327    iterator insert(const_iterator hint, value_type&& obj);
328    template <class InputIterator>
329        void insert(InputIterator first, InputIterator last);
330    void insert(initializer_list<value_type>);
331
332    node_type extract(const_iterator position);             // C++17
333    node_type extract(const key_type& x);                   // C++17
334    iterator insert(node_type&& nh);                        // C++17
335    iterator insert(const_iterator hint, node_type&& nh);   // C++17
336
337    iterator erase(const_iterator position);
338    iterator erase(iterator position);  // C++14
339    size_type erase(const key_type& k);
340    iterator erase(const_iterator first, const_iterator last);
341    void clear() noexcept;
342
343    template<class H2, class P2>
344      void merge(unordered_multiset<Key, H2, P2, Allocator>& source);    // C++17
345    template<class H2, class P2>
346      void merge(unordered_multiset<Key, H2, P2, Allocator>&& source);   // C++17
347    template<class H2, class P2>
348      void merge(unordered_set<Key, H2, P2, Allocator>& source);         // C++17
349    template<class H2, class P2>
350      void merge(unordered_set<Key, H2, P2, Allocator>&& source);        // C++17
351
352    void swap(unordered_multiset&)
353       noexcept(allocator_traits<Allocator>::is_always_equal::value &&
354                 noexcept(swap(declval<hasher&>(), declval<hasher&>())) &&
355                 noexcept(swap(declval<key_equal&>(), declval<key_equal&>()))); // C++17
356
357    hasher hash_function() const;
358    key_equal key_eq() const;
359
360    iterator       find(const key_type& k);
361    const_iterator find(const key_type& k) const;
362    template<typename K>
363        iterator find(const K& x);              // C++20
364    template<typename K>
365        const_iterator find(const K& x) const;  // C++20
366    size_type count(const key_type& k) const;
367    template<typename K>
368        size_type count(const K& k) const; // C++20
369    bool contains(const key_type& k) const; // C++20
370    template<typename K>
371        bool contains(const K& k) const; // C++20
372    pair<iterator, iterator>             equal_range(const key_type& k);
373    pair<const_iterator, const_iterator> equal_range(const key_type& k) const;
374    template<typename K>
375        pair<iterator, iterator>             equal_range(const K& k); // C++20
376    template<typename K>
377        pair<const_iterator, const_iterator> equal_range(const K& k) const; // C++20
378
379    size_type bucket_count() const noexcept;
380    size_type max_bucket_count() const noexcept;
381
382    size_type bucket_size(size_type n) const;
383    size_type bucket(const key_type& k) const;
384
385    local_iterator       begin(size_type n);
386    local_iterator       end(size_type n);
387    const_local_iterator begin(size_type n) const;
388    const_local_iterator end(size_type n) const;
389    const_local_iterator cbegin(size_type n) const;
390    const_local_iterator cend(size_type n) const;
391
392    float load_factor() const noexcept;
393    float max_load_factor() const noexcept;
394    void max_load_factor(float z);
395    void rehash(size_type n);
396    void reserve(size_type n);
397};
398
399template<class InputIterator,
400    class Hash = hash<typename iterator_traits<InputIterator>::value_type>,
401    class Pred = equal_to<typename iterator_traits<InputIterator>::value_type>,
402    class Allocator = allocator<typename iterator_traits<InputIterator>::value_type>>
403unordered_multiset(InputIterator, InputIterator, see below::size_type = see below,
404    Hash = Hash(), Pred = Pred(), Allocator = Allocator())
405  -> unordered_multiset<typename iterator_traits<InputIterator>::value_type,
406        Hash, Pred, Allocator>; // C++17
407
408template<class T, class Hash = hash<T>,
409          class Pred = equal_to<T>, class Allocator = allocator<T>>
410unordered_multiset(initializer_list<T>, typename see below::size_type = see below,
411    Hash = Hash(), Pred = Pred(), Allocator = Allocator())
412  -> unordered_multiset<T, Hash, Pred, Allocator>; // C++17
413
414template<class InputIterator,  class Allocator>
415unordered_multiset(InputIterator, InputIterator, typename see below::size_type, Allocator)
416  -> unordered_multiset<typename iterator_traits<InputIterator>::value_type,
417        hash<typename iterator_traits<InputIterator>::value_type>,
418        equal_to<typename iterator_traits<InputIterator>::value_type>,
419        Allocator>; // C++17
420
421template<class InputIterator,  class Hash, class Allocator>
422unordered_multiset(InputIterator, InputIterator, typename see below::size_type,
423    Hash, Allocator)
424  -> unordered_multiset<typename iterator_traits<InputIterator>::value_type, Hash,
425        equal_to<typename iterator_traits<InputIterator>::value_type>, Allocator>; // C++17
426
427template<class T, class Allocator>
428unordered_multiset(initializer_list<T>, typename see below::size_type, Allocator)
429  -> unordered_multiset<T, hash<T>, equal_to<T>, Allocator>; // C++17
430
431template<class T, class Hash, class Allocator>
432unordered_multiset(initializer_list<T>, typename see below::size_type, Hash, Allocator)
433  -> unordered_multiset<T, Hash, equal_to<T>, Allocator>; // C++17
434
435template <class Value, class Hash, class Pred, class Alloc>
436    void swap(unordered_multiset<Value, Hash, Pred, Alloc>& x,
437              unordered_multiset<Value, Hash, Pred, Alloc>& y)
438              noexcept(noexcept(x.swap(y)));
439
440template <class K, class T, class H, class P, class A, class Predicate>
441    typename unordered_set<K, T, H, P, A>::size_type
442    erase_if(unordered_set<K, T, H, P, A>& c, Predicate pred);       // C++20
443
444template <class K, class T, class H, class P, class A, class Predicate>
445    typename unordered_multiset<K, T, H, P, A>::size_type
446    erase_if(unordered_multiset<K, T, H, P, A>& c, Predicate pred);  // C++20
447
448
449template <class Value, class Hash, class Pred, class Alloc>
450    bool
451    operator==(const unordered_multiset<Value, Hash, Pred, Alloc>& x,
452               const unordered_multiset<Value, Hash, Pred, Alloc>& y);
453
454template <class Value, class Hash, class Pred, class Alloc>
455    bool
456    operator!=(const unordered_multiset<Value, Hash, Pred, Alloc>& x,
457               const unordered_multiset<Value, Hash, Pred, Alloc>& y);
458}  // std
459
460*/
461
462#include <__config>
463#include <__debug>
464#include <__functional/is_transparent.h>
465#include <__hash_table>
466#include <__node_handle>
467#include <__utility/forward.h>
468#include <compare>
469#include <functional>
470#include <iterator> // __libcpp_erase_if_container
471#include <version>
472
473#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
474#pragma GCC system_header
475#endif
476
477_LIBCPP_BEGIN_NAMESPACE_STD
478
479template <class _Value, class _Hash, class _Pred, class _Alloc>
480class unordered_multiset;
481
482template <class _Value, class _Hash = hash<_Value>, class _Pred = equal_to<_Value>,
483          class _Alloc = allocator<_Value> >
484class _LIBCPP_TEMPLATE_VIS unordered_set
485{
486public:
487    // types
488    typedef _Value                                                     key_type;
489    typedef key_type                                                   value_type;
490    typedef __identity_t<_Hash>                                        hasher;
491    typedef __identity_t<_Pred>                                        key_equal;
492    typedef __identity_t<_Alloc>                                       allocator_type;
493    typedef value_type&                                                reference;
494    typedef const value_type&                                          const_reference;
495    static_assert((is_same<value_type, typename allocator_type::value_type>::value),
496                  "Invalid allocator::value_type");
497
498private:
499    typedef __hash_table<value_type, hasher, key_equal, allocator_type> __table;
500
501    __table __table_;
502
503public:
504    typedef typename __table::pointer         pointer;
505    typedef typename __table::const_pointer   const_pointer;
506    typedef typename __table::size_type       size_type;
507    typedef typename __table::difference_type difference_type;
508
509    typedef typename __table::const_iterator       iterator;
510    typedef typename __table::const_iterator       const_iterator;
511    typedef typename __table::const_local_iterator local_iterator;
512    typedef typename __table::const_local_iterator const_local_iterator;
513
514#if _LIBCPP_STD_VER > 14
515    typedef __set_node_handle<typename __table::__node, allocator_type> node_type;
516    typedef __insert_return_type<iterator, node_type> insert_return_type;
517#endif
518
519    template <class _Value2, class _Hash2, class _Pred2, class _Alloc2>
520        friend class _LIBCPP_TEMPLATE_VIS unordered_set;
521    template <class _Value2, class _Hash2, class _Pred2, class _Alloc2>
522        friend class _LIBCPP_TEMPLATE_VIS unordered_multiset;
523
524    _LIBCPP_INLINE_VISIBILITY
525    unordered_set()
526        _NOEXCEPT_(is_nothrow_default_constructible<__table>::value)
527        {
528#if _LIBCPP_DEBUG_LEVEL == 2
529            __get_db()->__insert_c(this);
530#endif
531        }
532    explicit unordered_set(size_type __n, const hasher& __hf = hasher(),
533                           const key_equal& __eql = key_equal());
534#if _LIBCPP_STD_VER > 11
535    inline _LIBCPP_INLINE_VISIBILITY
536    unordered_set(size_type __n, const allocator_type& __a)
537        : unordered_set(__n, hasher(), key_equal(), __a) {}
538    inline _LIBCPP_INLINE_VISIBILITY
539    unordered_set(size_type __n, const hasher& __hf, const allocator_type& __a)
540        : unordered_set(__n, __hf, key_equal(), __a) {}
541#endif
542    unordered_set(size_type __n, const hasher& __hf, const key_equal& __eql,
543                  const allocator_type& __a);
544    template <class _InputIterator>
545        unordered_set(_InputIterator __first, _InputIterator __last);
546    template <class _InputIterator>
547        unordered_set(_InputIterator __first, _InputIterator __last,
548                      size_type __n, const hasher& __hf = hasher(),
549                      const key_equal& __eql = key_equal());
550    template <class _InputIterator>
551        unordered_set(_InputIterator __first, _InputIterator __last,
552                      size_type __n, const hasher& __hf, const key_equal& __eql,
553                      const allocator_type& __a);
554#if _LIBCPP_STD_VER > 11
555    template <class _InputIterator>
556    inline _LIBCPP_INLINE_VISIBILITY
557        unordered_set(_InputIterator __first, _InputIterator __last,
558                    size_type __n, const allocator_type& __a)
559            : unordered_set(__first, __last, __n, hasher(), key_equal(), __a) {}
560    template <class _InputIterator>
561        unordered_set(_InputIterator __first, _InputIterator __last,
562                      size_type __n, const hasher& __hf, const allocator_type& __a)
563            : unordered_set(__first, __last, __n, __hf, key_equal(), __a) {}
564#endif
565    _LIBCPP_INLINE_VISIBILITY
566    explicit unordered_set(const allocator_type& __a);
567    unordered_set(const unordered_set& __u);
568    unordered_set(const unordered_set& __u, const allocator_type& __a);
569#ifndef _LIBCPP_CXX03_LANG
570    _LIBCPP_INLINE_VISIBILITY
571    unordered_set(unordered_set&& __u)
572        _NOEXCEPT_(is_nothrow_move_constructible<__table>::value);
573    unordered_set(unordered_set&& __u, const allocator_type& __a);
574    unordered_set(initializer_list<value_type> __il);
575    unordered_set(initializer_list<value_type> __il, size_type __n,
576                  const hasher& __hf = hasher(),
577                  const key_equal& __eql = key_equal());
578    unordered_set(initializer_list<value_type> __il, size_type __n,
579                  const hasher& __hf, const key_equal& __eql,
580                  const allocator_type& __a);
581#if _LIBCPP_STD_VER > 11
582    inline _LIBCPP_INLINE_VISIBILITY
583    unordered_set(initializer_list<value_type> __il, size_type __n,
584                                                      const allocator_type& __a)
585        : unordered_set(__il, __n, hasher(), key_equal(), __a) {}
586    inline _LIBCPP_INLINE_VISIBILITY
587    unordered_set(initializer_list<value_type> __il, size_type __n,
588                                  const hasher& __hf, const allocator_type& __a)
589        : unordered_set(__il, __n, __hf, key_equal(), __a) {}
590#endif
591#endif // _LIBCPP_CXX03_LANG
592    _LIBCPP_INLINE_VISIBILITY
593    ~unordered_set() {
594        static_assert(sizeof(__diagnose_unordered_container_requirements<_Value, _Hash, _Pred>(0)), "");
595    }
596
597    _LIBCPP_INLINE_VISIBILITY
598    unordered_set& operator=(const unordered_set& __u)
599    {
600        __table_ = __u.__table_;
601        return *this;
602    }
603#ifndef _LIBCPP_CXX03_LANG
604    _LIBCPP_INLINE_VISIBILITY
605    unordered_set& operator=(unordered_set&& __u)
606        _NOEXCEPT_(is_nothrow_move_assignable<__table>::value);
607    _LIBCPP_INLINE_VISIBILITY
608    unordered_set& operator=(initializer_list<value_type> __il);
609#endif // _LIBCPP_CXX03_LANG
610
611    _LIBCPP_INLINE_VISIBILITY
612    allocator_type get_allocator() const _NOEXCEPT
613        {return allocator_type(__table_.__node_alloc());}
614
615    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
616    bool      empty() const _NOEXCEPT {return __table_.size() == 0;}
617    _LIBCPP_INLINE_VISIBILITY
618    size_type size() const _NOEXCEPT  {return __table_.size();}
619    _LIBCPP_INLINE_VISIBILITY
620    size_type max_size() const _NOEXCEPT {return __table_.max_size();}
621
622    _LIBCPP_INLINE_VISIBILITY
623    iterator       begin() _NOEXCEPT        {return __table_.begin();}
624    _LIBCPP_INLINE_VISIBILITY
625    iterator       end() _NOEXCEPT          {return __table_.end();}
626    _LIBCPP_INLINE_VISIBILITY
627    const_iterator begin()  const _NOEXCEPT {return __table_.begin();}
628    _LIBCPP_INLINE_VISIBILITY
629    const_iterator end()    const _NOEXCEPT {return __table_.end();}
630    _LIBCPP_INLINE_VISIBILITY
631    const_iterator cbegin() const _NOEXCEPT {return __table_.begin();}
632    _LIBCPP_INLINE_VISIBILITY
633    const_iterator cend()   const _NOEXCEPT {return __table_.end();}
634
635#ifndef _LIBCPP_CXX03_LANG
636    template <class... _Args>
637        _LIBCPP_INLINE_VISIBILITY
638        pair<iterator, bool> emplace(_Args&&... __args)
639            {return __table_.__emplace_unique(_VSTD::forward<_Args>(__args)...);}
640    template <class... _Args>
641        _LIBCPP_INLINE_VISIBILITY
642#if _LIBCPP_DEBUG_LEVEL == 2
643        iterator emplace_hint(const_iterator __p, _Args&&... __args)
644        {
645            _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__p) == this,
646                "unordered_set::emplace_hint(const_iterator, args...) called with an iterator not"
647                " referring to this unordered_set");
648            return __table_.__emplace_unique(_VSTD::forward<_Args>(__args)...).first;
649        }
650#else
651        iterator emplace_hint(const_iterator, _Args&&... __args)
652            {return __table_.__emplace_unique(_VSTD::forward<_Args>(__args)...).first;}
653#endif
654
655    _LIBCPP_INLINE_VISIBILITY
656    pair<iterator, bool> insert(value_type&& __x)
657        {return __table_.__insert_unique(_VSTD::move(__x));}
658    _LIBCPP_INLINE_VISIBILITY
659#if _LIBCPP_DEBUG_LEVEL == 2
660    iterator insert(const_iterator __p, value_type&& __x)
661        {
662            _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__p) == this,
663                "unordered_set::insert(const_iterator, value_type&&) called with an iterator not"
664                " referring to this unordered_set");
665            return insert(_VSTD::move(__x)).first;
666        }
667#else
668    iterator insert(const_iterator, value_type&& __x)
669        {return insert(_VSTD::move(__x)).first;}
670#endif
671    _LIBCPP_INLINE_VISIBILITY
672    void insert(initializer_list<value_type> __il)
673        {insert(__il.begin(), __il.end());}
674#endif // _LIBCPP_CXX03_LANG
675    _LIBCPP_INLINE_VISIBILITY
676    pair<iterator, bool> insert(const value_type& __x)
677        {return __table_.__insert_unique(__x);}
678
679    _LIBCPP_INLINE_VISIBILITY
680#if _LIBCPP_DEBUG_LEVEL == 2
681    iterator insert(const_iterator __p, const value_type& __x)
682        {
683            _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__p) == this,
684                "unordered_set::insert(const_iterator, const value_type&) called with an iterator not"
685                " referring to this unordered_set");
686            return insert(__x).first;
687        }
688#else
689    iterator insert(const_iterator, const value_type& __x)
690        {return insert(__x).first;}
691#endif
692    template <class _InputIterator>
693        _LIBCPP_INLINE_VISIBILITY
694        void insert(_InputIterator __first, _InputIterator __last);
695
696    _LIBCPP_INLINE_VISIBILITY
697    iterator erase(const_iterator __p) {return __table_.erase(__p);}
698    _LIBCPP_INLINE_VISIBILITY
699    size_type erase(const key_type& __k) {return __table_.__erase_unique(__k);}
700    _LIBCPP_INLINE_VISIBILITY
701    iterator erase(const_iterator __first, const_iterator __last)
702        {return __table_.erase(__first, __last);}
703    _LIBCPP_INLINE_VISIBILITY
704    void clear() _NOEXCEPT {__table_.clear();}
705
706#if _LIBCPP_STD_VER > 14
707    _LIBCPP_INLINE_VISIBILITY
708    insert_return_type insert(node_type&& __nh)
709    {
710        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
711            "node_type with incompatible allocator passed to unordered_set::insert()");
712        return __table_.template __node_handle_insert_unique<
713            node_type, insert_return_type>(_VSTD::move(__nh));
714    }
715    _LIBCPP_INLINE_VISIBILITY
716    iterator insert(const_iterator __h, node_type&& __nh)
717    {
718        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
719            "node_type with incompatible allocator passed to unordered_set::insert()");
720        return __table_.template __node_handle_insert_unique<node_type>(
721            __h, _VSTD::move(__nh));
722    }
723    _LIBCPP_INLINE_VISIBILITY
724    node_type extract(key_type const& __key)
725    {
726        return __table_.template __node_handle_extract<node_type>(__key);
727    }
728    _LIBCPP_INLINE_VISIBILITY
729    node_type extract(const_iterator __it)
730    {
731        return __table_.template __node_handle_extract<node_type>(__it);
732    }
733
734    template<class _H2, class _P2>
735    _LIBCPP_INLINE_VISIBILITY
736    void merge(unordered_set<key_type, _H2, _P2, allocator_type>& __source)
737    {
738        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
739                       "merging container with incompatible allocator");
740        __table_.__node_handle_merge_unique(__source.__table_);
741    }
742    template<class _H2, class _P2>
743    _LIBCPP_INLINE_VISIBILITY
744    void merge(unordered_set<key_type, _H2, _P2, allocator_type>&& __source)
745    {
746        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
747                       "merging container with incompatible allocator");
748        __table_.__node_handle_merge_unique(__source.__table_);
749    }
750    template<class _H2, class _P2>
751    _LIBCPP_INLINE_VISIBILITY
752    void merge(unordered_multiset<key_type, _H2, _P2, allocator_type>& __source)
753    {
754        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
755                       "merging container with incompatible allocator");
756        __table_.__node_handle_merge_unique(__source.__table_);
757    }
758    template<class _H2, class _P2>
759    _LIBCPP_INLINE_VISIBILITY
760    void merge(unordered_multiset<key_type, _H2, _P2, allocator_type>&& __source)
761    {
762        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
763                       "merging container with incompatible allocator");
764        __table_.__node_handle_merge_unique(__source.__table_);
765    }
766#endif
767
768    _LIBCPP_INLINE_VISIBILITY
769    void swap(unordered_set& __u)
770        _NOEXCEPT_(__is_nothrow_swappable<__table>::value)
771        {__table_.swap(__u.__table_);}
772
773    _LIBCPP_INLINE_VISIBILITY
774    hasher hash_function() const {return __table_.hash_function();}
775    _LIBCPP_INLINE_VISIBILITY
776    key_equal key_eq() const {return __table_.key_eq();}
777
778    _LIBCPP_INLINE_VISIBILITY
779    iterator       find(const key_type& __k)       {return __table_.find(__k);}
780    _LIBCPP_INLINE_VISIBILITY
781    const_iterator find(const key_type& __k) const {return __table_.find(__k);}
782#if _LIBCPP_STD_VER > 17
783    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
784    _LIBCPP_INLINE_VISIBILITY
785    iterator       find(const _K2& __k)            {return __table_.find(__k);}
786    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
787    _LIBCPP_INLINE_VISIBILITY
788    const_iterator find(const _K2& __k) const      {return __table_.find(__k);}
789#endif // _LIBCPP_STD_VER > 17
790
791    _LIBCPP_INLINE_VISIBILITY
792    size_type count(const key_type& __k) const {return __table_.__count_unique(__k);}
793#if _LIBCPP_STD_VER > 17
794    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
795    _LIBCPP_INLINE_VISIBILITY
796    size_type count(const _K2& __k) const      {return __table_.__count_unique(__k);}
797#endif // _LIBCPP_STD_VER > 17
798
799#if _LIBCPP_STD_VER > 17
800    _LIBCPP_INLINE_VISIBILITY
801    bool contains(const key_type& __k) const {return find(__k) != end();}
802
803    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
804    _LIBCPP_INLINE_VISIBILITY
805    bool contains(const _K2& __k) const      {return find(__k) != end();}
806#endif // _LIBCPP_STD_VER > 17
807
808    _LIBCPP_INLINE_VISIBILITY
809    pair<iterator, iterator>             equal_range(const key_type& __k)
810        {return __table_.__equal_range_unique(__k);}
811    _LIBCPP_INLINE_VISIBILITY
812    pair<const_iterator, const_iterator> equal_range(const key_type& __k) const
813        {return __table_.__equal_range_unique(__k);}
814#if _LIBCPP_STD_VER > 17
815    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
816    _LIBCPP_INLINE_VISIBILITY
817    pair<iterator, iterator>             equal_range(const _K2& __k)
818        {return __table_.__equal_range_unique(__k);}
819    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
820    _LIBCPP_INLINE_VISIBILITY
821    pair<const_iterator, const_iterator> equal_range(const _K2& __k) const
822        {return __table_.__equal_range_unique(__k);}
823#endif // _LIBCPP_STD_VER > 17
824
825    _LIBCPP_INLINE_VISIBILITY
826    size_type bucket_count() const _NOEXCEPT {return __table_.bucket_count();}
827    _LIBCPP_INLINE_VISIBILITY
828    size_type max_bucket_count() const _NOEXCEPT {return __table_.max_bucket_count();}
829
830    _LIBCPP_INLINE_VISIBILITY
831    size_type bucket_size(size_type __n) const {return __table_.bucket_size(__n);}
832    _LIBCPP_INLINE_VISIBILITY
833    size_type bucket(const key_type& __k) const {return __table_.bucket(__k);}
834
835    _LIBCPP_INLINE_VISIBILITY
836    local_iterator       begin(size_type __n)        {return __table_.begin(__n);}
837    _LIBCPP_INLINE_VISIBILITY
838    local_iterator       end(size_type __n)          {return __table_.end(__n);}
839    _LIBCPP_INLINE_VISIBILITY
840    const_local_iterator begin(size_type __n) const  {return __table_.cbegin(__n);}
841    _LIBCPP_INLINE_VISIBILITY
842    const_local_iterator end(size_type __n) const    {return __table_.cend(__n);}
843    _LIBCPP_INLINE_VISIBILITY
844    const_local_iterator cbegin(size_type __n) const {return __table_.cbegin(__n);}
845    _LIBCPP_INLINE_VISIBILITY
846    const_local_iterator cend(size_type __n) const   {return __table_.cend(__n);}
847
848    _LIBCPP_INLINE_VISIBILITY
849    float load_factor() const _NOEXCEPT {return __table_.load_factor();}
850    _LIBCPP_INLINE_VISIBILITY
851    float max_load_factor() const _NOEXCEPT {return __table_.max_load_factor();}
852    _LIBCPP_INLINE_VISIBILITY
853    void max_load_factor(float __mlf) {__table_.max_load_factor(__mlf);}
854    _LIBCPP_INLINE_VISIBILITY
855    void rehash(size_type __n) {__table_.rehash(__n);}
856    _LIBCPP_INLINE_VISIBILITY
857    void reserve(size_type __n) {__table_.reserve(__n);}
858
859#if _LIBCPP_DEBUG_LEVEL == 2
860
861    bool __dereferenceable(const const_iterator* __i) const
862        {return __table_.__dereferenceable(__i);}
863    bool __decrementable(const const_iterator* __i) const
864        {return __table_.__decrementable(__i);}
865    bool __addable(const const_iterator* __i, ptrdiff_t __n) const
866        {return __table_.__addable(__i, __n);}
867    bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const
868        {return __table_.__addable(__i, __n);}
869
870#endif // _LIBCPP_DEBUG_LEVEL == 2
871
872};
873
874#if _LIBCPP_STD_VER >= 17
875template<class _InputIterator,
876         class _Hash = hash<__iter_value_type<_InputIterator>>,
877         class _Pred = equal_to<__iter_value_type<_InputIterator>>,
878         class _Allocator = allocator<__iter_value_type<_InputIterator>>,
879         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
880         class = enable_if_t<!__is_allocator<_Hash>::value>,
881         class = enable_if_t<!is_integral<_Hash>::value>,
882         class = enable_if_t<!__is_allocator<_Pred>::value>,
883         class = enable_if_t<__is_allocator<_Allocator>::value>>
884unordered_set(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type = 0,
885              _Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator())
886  -> unordered_set<__iter_value_type<_InputIterator>, _Hash, _Pred, _Allocator>;
887
888template<class _Tp, class _Hash = hash<_Tp>,
889         class _Pred = equal_to<_Tp>,
890         class _Allocator = allocator<_Tp>,
891         class = enable_if_t<!__is_allocator<_Hash>::value>,
892         class = enable_if_t<!is_integral<_Hash>::value>,
893         class = enable_if_t<!__is_allocator<_Pred>::value>,
894         class = enable_if_t<__is_allocator<_Allocator>::value>>
895unordered_set(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type = 0,
896              _Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator())
897  -> unordered_set<_Tp, _Hash, _Pred, _Allocator>;
898
899template<class _InputIterator, class _Allocator,
900         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
901         class = enable_if_t<__is_allocator<_Allocator>::value>>
902unordered_set(_InputIterator, _InputIterator,
903              typename allocator_traits<_Allocator>::size_type, _Allocator)
904  -> unordered_set<__iter_value_type<_InputIterator>,
905                   hash<__iter_value_type<_InputIterator>>,
906                   equal_to<__iter_value_type<_InputIterator>>,
907                   _Allocator>;
908
909template<class _InputIterator, class _Hash, class _Allocator,
910         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
911         class = enable_if_t<!__is_allocator<_Hash>::value>,
912         class = enable_if_t<!is_integral<_Hash>::value>,
913         class = enable_if_t<__is_allocator<_Allocator>::value>>
914unordered_set(_InputIterator, _InputIterator,
915              typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
916  -> unordered_set<__iter_value_type<_InputIterator>, _Hash,
917                   equal_to<__iter_value_type<_InputIterator>>,
918                   _Allocator>;
919
920template<class _Tp, class _Allocator,
921         class = enable_if_t<__is_allocator<_Allocator>::value>>
922unordered_set(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type, _Allocator)
923  -> unordered_set<_Tp, hash<_Tp>, equal_to<_Tp>, _Allocator>;
924
925template<class _Tp, class _Hash, class _Allocator,
926         class = enable_if_t<!__is_allocator<_Hash>::value>,
927         class = enable_if_t<!is_integral<_Hash>::value>,
928         class = enable_if_t<__is_allocator<_Allocator>::value>>
929unordered_set(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
930  -> unordered_set<_Tp, _Hash, equal_to<_Tp>, _Allocator>;
931#endif
932
933template <class _Value, class _Hash, class _Pred, class _Alloc>
934unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(size_type __n,
935        const hasher& __hf, const key_equal& __eql)
936    : __table_(__hf, __eql)
937{
938#if _LIBCPP_DEBUG_LEVEL == 2
939    __get_db()->__insert_c(this);
940#endif
941    __table_.rehash(__n);
942}
943
944template <class _Value, class _Hash, class _Pred, class _Alloc>
945unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(size_type __n,
946        const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
947    : __table_(__hf, __eql, __a)
948{
949#if _LIBCPP_DEBUG_LEVEL == 2
950    __get_db()->__insert_c(this);
951#endif
952    __table_.rehash(__n);
953}
954
955template <class _Value, class _Hash, class _Pred, class _Alloc>
956template <class _InputIterator>
957unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
958        _InputIterator __first, _InputIterator __last)
959{
960#if _LIBCPP_DEBUG_LEVEL == 2
961    __get_db()->__insert_c(this);
962#endif
963    insert(__first, __last);
964}
965
966template <class _Value, class _Hash, class _Pred, class _Alloc>
967template <class _InputIterator>
968unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
969        _InputIterator __first, _InputIterator __last, size_type __n,
970        const hasher& __hf, const key_equal& __eql)
971    : __table_(__hf, __eql)
972{
973#if _LIBCPP_DEBUG_LEVEL == 2
974    __get_db()->__insert_c(this);
975#endif
976    __table_.rehash(__n);
977    insert(__first, __last);
978}
979
980template <class _Value, class _Hash, class _Pred, class _Alloc>
981template <class _InputIterator>
982unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
983        _InputIterator __first, _InputIterator __last, size_type __n,
984        const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
985    : __table_(__hf, __eql, __a)
986{
987#if _LIBCPP_DEBUG_LEVEL == 2
988    __get_db()->__insert_c(this);
989#endif
990    __table_.rehash(__n);
991    insert(__first, __last);
992}
993
994template <class _Value, class _Hash, class _Pred, class _Alloc>
995inline
996unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
997        const allocator_type& __a)
998    : __table_(__a)
999{
1000#if _LIBCPP_DEBUG_LEVEL == 2
1001    __get_db()->__insert_c(this);
1002#endif
1003}
1004
1005template <class _Value, class _Hash, class _Pred, class _Alloc>
1006unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
1007        const unordered_set& __u)
1008    : __table_(__u.__table_)
1009{
1010#if _LIBCPP_DEBUG_LEVEL == 2
1011    __get_db()->__insert_c(this);
1012#endif
1013    __table_.rehash(__u.bucket_count());
1014    insert(__u.begin(), __u.end());
1015}
1016
1017template <class _Value, class _Hash, class _Pred, class _Alloc>
1018unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
1019        const unordered_set& __u, const allocator_type& __a)
1020    : __table_(__u.__table_, __a)
1021{
1022#if _LIBCPP_DEBUG_LEVEL == 2
1023    __get_db()->__insert_c(this);
1024#endif
1025    __table_.rehash(__u.bucket_count());
1026    insert(__u.begin(), __u.end());
1027}
1028
1029#ifndef _LIBCPP_CXX03_LANG
1030
1031template <class _Value, class _Hash, class _Pred, class _Alloc>
1032inline
1033unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
1034        unordered_set&& __u)
1035    _NOEXCEPT_(is_nothrow_move_constructible<__table>::value)
1036    : __table_(_VSTD::move(__u.__table_))
1037{
1038#if _LIBCPP_DEBUG_LEVEL == 2
1039    __get_db()->__insert_c(this);
1040    __get_db()->swap(this, &__u);
1041#endif
1042}
1043
1044template <class _Value, class _Hash, class _Pred, class _Alloc>
1045unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
1046        unordered_set&& __u, const allocator_type& __a)
1047    : __table_(_VSTD::move(__u.__table_), __a)
1048{
1049#if _LIBCPP_DEBUG_LEVEL == 2
1050    __get_db()->__insert_c(this);
1051#endif
1052    if (__a != __u.get_allocator())
1053    {
1054        iterator __i = __u.begin();
1055        while (__u.size() != 0)
1056            __table_.__insert_unique(_VSTD::move(__u.__table_.remove(__i++)->__value_));
1057    }
1058#if _LIBCPP_DEBUG_LEVEL == 2
1059    else
1060        __get_db()->swap(this, &__u);
1061#endif
1062}
1063
1064template <class _Value, class _Hash, class _Pred, class _Alloc>
1065unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
1066        initializer_list<value_type> __il)
1067{
1068#if _LIBCPP_DEBUG_LEVEL == 2
1069    __get_db()->__insert_c(this);
1070#endif
1071    insert(__il.begin(), __il.end());
1072}
1073
1074template <class _Value, class _Hash, class _Pred, class _Alloc>
1075unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
1076        initializer_list<value_type> __il, size_type __n, const hasher& __hf,
1077        const key_equal& __eql)
1078    : __table_(__hf, __eql)
1079{
1080#if _LIBCPP_DEBUG_LEVEL == 2
1081    __get_db()->__insert_c(this);
1082#endif
1083    __table_.rehash(__n);
1084    insert(__il.begin(), __il.end());
1085}
1086
1087template <class _Value, class _Hash, class _Pred, class _Alloc>
1088unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
1089        initializer_list<value_type> __il, size_type __n, const hasher& __hf,
1090        const key_equal& __eql, const allocator_type& __a)
1091    : __table_(__hf, __eql, __a)
1092{
1093#if _LIBCPP_DEBUG_LEVEL == 2
1094    __get_db()->__insert_c(this);
1095#endif
1096    __table_.rehash(__n);
1097    insert(__il.begin(), __il.end());
1098}
1099
1100template <class _Value, class _Hash, class _Pred, class _Alloc>
1101inline
1102unordered_set<_Value, _Hash, _Pred, _Alloc>&
1103unordered_set<_Value, _Hash, _Pred, _Alloc>::operator=(unordered_set&& __u)
1104    _NOEXCEPT_(is_nothrow_move_assignable<__table>::value)
1105{
1106    __table_ = _VSTD::move(__u.__table_);
1107    return *this;
1108}
1109
1110template <class _Value, class _Hash, class _Pred, class _Alloc>
1111inline
1112unordered_set<_Value, _Hash, _Pred, _Alloc>&
1113unordered_set<_Value, _Hash, _Pred, _Alloc>::operator=(
1114        initializer_list<value_type> __il)
1115{
1116    __table_.__assign_unique(__il.begin(), __il.end());
1117    return *this;
1118}
1119
1120#endif // _LIBCPP_CXX03_LANG
1121
1122template <class _Value, class _Hash, class _Pred, class _Alloc>
1123template <class _InputIterator>
1124inline
1125void
1126unordered_set<_Value, _Hash, _Pred, _Alloc>::insert(_InputIterator __first,
1127                                                    _InputIterator __last)
1128{
1129    for (; __first != __last; ++__first)
1130        __table_.__insert_unique(*__first);
1131}
1132
1133template <class _Value, class _Hash, class _Pred, class _Alloc>
1134inline _LIBCPP_INLINE_VISIBILITY
1135void
1136swap(unordered_set<_Value, _Hash, _Pred, _Alloc>& __x,
1137     unordered_set<_Value, _Hash, _Pred, _Alloc>& __y)
1138    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
1139{
1140    __x.swap(__y);
1141}
1142
1143#if _LIBCPP_STD_VER > 17
1144template <class _Value, class _Hash, class _Pred, class _Alloc,
1145          class _Predicate>
1146inline _LIBCPP_INLINE_VISIBILITY
1147    typename unordered_set<_Value, _Hash, _Pred, _Alloc>::size_type
1148    erase_if(unordered_set<_Value, _Hash, _Pred, _Alloc>& __c,
1149             _Predicate __pred) {
1150  return _VSTD::__libcpp_erase_if_container(__c, __pred);
1151}
1152#endif
1153
1154template <class _Value, class _Hash, class _Pred, class _Alloc>
1155bool
1156operator==(const unordered_set<_Value, _Hash, _Pred, _Alloc>& __x,
1157           const unordered_set<_Value, _Hash, _Pred, _Alloc>& __y)
1158{
1159    if (__x.size() != __y.size())
1160        return false;
1161    typedef typename unordered_set<_Value, _Hash, _Pred, _Alloc>::const_iterator
1162                                                                 const_iterator;
1163    for (const_iterator __i = __x.begin(), __ex = __x.end(), __ey = __y.end();
1164            __i != __ex; ++__i)
1165    {
1166        const_iterator __j = __y.find(*__i);
1167        if (__j == __ey || !(*__i == *__j))
1168            return false;
1169    }
1170    return true;
1171}
1172
1173template <class _Value, class _Hash, class _Pred, class _Alloc>
1174inline _LIBCPP_INLINE_VISIBILITY
1175bool
1176operator!=(const unordered_set<_Value, _Hash, _Pred, _Alloc>& __x,
1177           const unordered_set<_Value, _Hash, _Pred, _Alloc>& __y)
1178{
1179    return !(__x == __y);
1180}
1181
1182template <class _Value, class _Hash = hash<_Value>, class _Pred = equal_to<_Value>,
1183          class _Alloc = allocator<_Value> >
1184class _LIBCPP_TEMPLATE_VIS unordered_multiset
1185{
1186public:
1187    // types
1188    typedef _Value                                                     key_type;
1189    typedef key_type                                                   value_type;
1190    typedef __identity_t<_Hash>                                        hasher;
1191    typedef __identity_t<_Pred>                                        key_equal;
1192    typedef __identity_t<_Alloc>                                       allocator_type;
1193    typedef value_type&                                                reference;
1194    typedef const value_type&                                          const_reference;
1195    static_assert((is_same<value_type, typename allocator_type::value_type>::value),
1196                  "Invalid allocator::value_type");
1197
1198private:
1199    typedef __hash_table<value_type, hasher, key_equal, allocator_type> __table;
1200
1201    __table __table_;
1202
1203public:
1204    typedef typename __table::pointer         pointer;
1205    typedef typename __table::const_pointer   const_pointer;
1206    typedef typename __table::size_type       size_type;
1207    typedef typename __table::difference_type difference_type;
1208
1209    typedef typename __table::const_iterator       iterator;
1210    typedef typename __table::const_iterator       const_iterator;
1211    typedef typename __table::const_local_iterator local_iterator;
1212    typedef typename __table::const_local_iterator const_local_iterator;
1213
1214#if _LIBCPP_STD_VER > 14
1215    typedef __set_node_handle<typename __table::__node, allocator_type> node_type;
1216#endif
1217
1218    template <class _Value2, class _Hash2, class _Pred2, class _Alloc2>
1219        friend class _LIBCPP_TEMPLATE_VIS unordered_set;
1220    template <class _Value2, class _Hash2, class _Pred2, class _Alloc2>
1221        friend class _LIBCPP_TEMPLATE_VIS unordered_multiset;
1222
1223    _LIBCPP_INLINE_VISIBILITY
1224    unordered_multiset()
1225        _NOEXCEPT_(is_nothrow_default_constructible<__table>::value)
1226        {
1227#if _LIBCPP_DEBUG_LEVEL == 2
1228            __get_db()->__insert_c(this);
1229#endif
1230        }
1231    explicit unordered_multiset(size_type __n, const hasher& __hf = hasher(),
1232                                const key_equal& __eql = key_equal());
1233    unordered_multiset(size_type __n, const hasher& __hf,
1234                       const key_equal& __eql, const allocator_type& __a);
1235#if _LIBCPP_STD_VER > 11
1236    inline _LIBCPP_INLINE_VISIBILITY
1237    unordered_multiset(size_type __n, const allocator_type& __a)
1238        : unordered_multiset(__n, hasher(), key_equal(), __a) {}
1239    inline _LIBCPP_INLINE_VISIBILITY
1240    unordered_multiset(size_type __n, const hasher& __hf, const allocator_type& __a)
1241        : unordered_multiset(__n, __hf, key_equal(), __a) {}
1242#endif
1243    template <class _InputIterator>
1244        unordered_multiset(_InputIterator __first, _InputIterator __last);
1245    template <class _InputIterator>
1246        unordered_multiset(_InputIterator __first, _InputIterator __last,
1247                      size_type __n, const hasher& __hf = hasher(),
1248                      const key_equal& __eql = key_equal());
1249    template <class _InputIterator>
1250        unordered_multiset(_InputIterator __first, _InputIterator __last,
1251                      size_type __n , const hasher& __hf,
1252                      const key_equal& __eql, const allocator_type& __a);
1253#if _LIBCPP_STD_VER > 11
1254    template <class _InputIterator>
1255    inline _LIBCPP_INLINE_VISIBILITY
1256    unordered_multiset(_InputIterator __first, _InputIterator __last,
1257                       size_type __n, const allocator_type& __a)
1258        : unordered_multiset(__first, __last, __n, hasher(), key_equal(), __a) {}
1259    template <class _InputIterator>
1260    inline _LIBCPP_INLINE_VISIBILITY
1261    unordered_multiset(_InputIterator __first, _InputIterator __last,
1262                       size_type __n, const hasher& __hf, const allocator_type& __a)
1263        : unordered_multiset(__first, __last, __n, __hf, key_equal(), __a) {}
1264#endif
1265    _LIBCPP_INLINE_VISIBILITY
1266    explicit unordered_multiset(const allocator_type& __a);
1267    unordered_multiset(const unordered_multiset& __u);
1268    unordered_multiset(const unordered_multiset& __u, const allocator_type& __a);
1269#ifndef _LIBCPP_CXX03_LANG
1270    _LIBCPP_INLINE_VISIBILITY
1271    unordered_multiset(unordered_multiset&& __u)
1272        _NOEXCEPT_(is_nothrow_move_constructible<__table>::value);
1273    unordered_multiset(unordered_multiset&& __u, const allocator_type& __a);
1274    unordered_multiset(initializer_list<value_type> __il);
1275    unordered_multiset(initializer_list<value_type> __il, size_type __n,
1276                       const hasher& __hf = hasher(),
1277                       const key_equal& __eql = key_equal());
1278    unordered_multiset(initializer_list<value_type> __il, size_type __n,
1279                       const hasher& __hf, const key_equal& __eql,
1280                       const allocator_type& __a);
1281#if _LIBCPP_STD_VER > 11
1282    inline _LIBCPP_INLINE_VISIBILITY
1283    unordered_multiset(initializer_list<value_type> __il, size_type __n, const allocator_type& __a)
1284      : unordered_multiset(__il, __n, hasher(), key_equal(), __a) {}
1285    inline _LIBCPP_INLINE_VISIBILITY
1286    unordered_multiset(initializer_list<value_type> __il, size_type __n, const hasher& __hf, const allocator_type& __a)
1287      : unordered_multiset(__il, __n, __hf, key_equal(), __a) {}
1288#endif
1289#endif // _LIBCPP_CXX03_LANG
1290    _LIBCPP_INLINE_VISIBILITY
1291    ~unordered_multiset() {
1292        static_assert(sizeof(__diagnose_unordered_container_requirements<_Value, _Hash, _Pred>(0)), "");
1293    }
1294
1295    _LIBCPP_INLINE_VISIBILITY
1296    unordered_multiset& operator=(const unordered_multiset& __u)
1297    {
1298        __table_ = __u.__table_;
1299        return *this;
1300    }
1301#ifndef _LIBCPP_CXX03_LANG
1302    _LIBCPP_INLINE_VISIBILITY
1303    unordered_multiset& operator=(unordered_multiset&& __u)
1304        _NOEXCEPT_(is_nothrow_move_assignable<__table>::value);
1305    unordered_multiset& operator=(initializer_list<value_type> __il);
1306#endif // _LIBCPP_CXX03_LANG
1307
1308    _LIBCPP_INLINE_VISIBILITY
1309    allocator_type get_allocator() const _NOEXCEPT
1310        {return allocator_type(__table_.__node_alloc());}
1311
1312    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
1313    bool      empty() const _NOEXCEPT {return __table_.size() == 0;}
1314    _LIBCPP_INLINE_VISIBILITY
1315    size_type size() const _NOEXCEPT  {return __table_.size();}
1316    _LIBCPP_INLINE_VISIBILITY
1317    size_type max_size() const _NOEXCEPT {return __table_.max_size();}
1318
1319    _LIBCPP_INLINE_VISIBILITY
1320    iterator       begin() _NOEXCEPT        {return __table_.begin();}
1321    _LIBCPP_INLINE_VISIBILITY
1322    iterator       end() _NOEXCEPT          {return __table_.end();}
1323    _LIBCPP_INLINE_VISIBILITY
1324    const_iterator begin()  const _NOEXCEPT {return __table_.begin();}
1325    _LIBCPP_INLINE_VISIBILITY
1326    const_iterator end()    const _NOEXCEPT {return __table_.end();}
1327    _LIBCPP_INLINE_VISIBILITY
1328    const_iterator cbegin() const _NOEXCEPT {return __table_.begin();}
1329    _LIBCPP_INLINE_VISIBILITY
1330    const_iterator cend()   const _NOEXCEPT {return __table_.end();}
1331
1332#ifndef _LIBCPP_CXX03_LANG
1333    template <class... _Args>
1334        _LIBCPP_INLINE_VISIBILITY
1335        iterator emplace(_Args&&... __args)
1336            {return __table_.__emplace_multi(_VSTD::forward<_Args>(__args)...);}
1337    template <class... _Args>
1338        _LIBCPP_INLINE_VISIBILITY
1339        iterator emplace_hint(const_iterator __p, _Args&&... __args)
1340            {return __table_.__emplace_hint_multi(__p, _VSTD::forward<_Args>(__args)...);}
1341
1342    _LIBCPP_INLINE_VISIBILITY
1343    iterator insert(value_type&& __x) {return __table_.__insert_multi(_VSTD::move(__x));}
1344    _LIBCPP_INLINE_VISIBILITY
1345    iterator insert(const_iterator __p, value_type&& __x)
1346        {return __table_.__insert_multi(__p, _VSTD::move(__x));}
1347    _LIBCPP_INLINE_VISIBILITY
1348    void insert(initializer_list<value_type> __il)
1349        {insert(__il.begin(), __il.end());}
1350#endif // _LIBCPP_CXX03_LANG
1351
1352    _LIBCPP_INLINE_VISIBILITY
1353    iterator insert(const value_type& __x) {return __table_.__insert_multi(__x);}
1354
1355    _LIBCPP_INLINE_VISIBILITY
1356    iterator insert(const_iterator __p, const value_type& __x)
1357        {return __table_.__insert_multi(__p, __x);}
1358
1359    template <class _InputIterator>
1360        _LIBCPP_INLINE_VISIBILITY
1361        void insert(_InputIterator __first, _InputIterator __last);
1362
1363#if _LIBCPP_STD_VER > 14
1364    _LIBCPP_INLINE_VISIBILITY
1365    iterator insert(node_type&& __nh)
1366    {
1367        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
1368            "node_type with incompatible allocator passed to unordered_multiset::insert()");
1369        return __table_.template __node_handle_insert_multi<node_type>(
1370            _VSTD::move(__nh));
1371    }
1372    _LIBCPP_INLINE_VISIBILITY
1373    iterator insert(const_iterator __hint, node_type&& __nh)
1374    {
1375        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
1376            "node_type with incompatible allocator passed to unordered_multiset::insert()");
1377        return __table_.template __node_handle_insert_multi<node_type>(
1378            __hint, _VSTD::move(__nh));
1379    }
1380    _LIBCPP_INLINE_VISIBILITY
1381    node_type extract(const_iterator __position)
1382    {
1383        return __table_.template __node_handle_extract<node_type>(
1384            __position);
1385    }
1386    _LIBCPP_INLINE_VISIBILITY
1387    node_type extract(key_type const& __key)
1388    {
1389        return __table_.template __node_handle_extract<node_type>(__key);
1390    }
1391
1392    template <class _H2, class _P2>
1393    _LIBCPP_INLINE_VISIBILITY
1394    void merge(unordered_multiset<key_type, _H2, _P2, allocator_type>& __source)
1395    {
1396        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
1397                       "merging container with incompatible allocator");
1398        return __table_.__node_handle_merge_multi(__source.__table_);
1399    }
1400    template <class _H2, class _P2>
1401    _LIBCPP_INLINE_VISIBILITY
1402    void merge(unordered_multiset<key_type, _H2, _P2, allocator_type>&& __source)
1403    {
1404        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
1405                       "merging container with incompatible allocator");
1406        return __table_.__node_handle_merge_multi(__source.__table_);
1407    }
1408    template <class _H2, class _P2>
1409    _LIBCPP_INLINE_VISIBILITY
1410    void merge(unordered_set<key_type, _H2, _P2, allocator_type>& __source)
1411    {
1412        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
1413                       "merging container with incompatible allocator");
1414        return __table_.__node_handle_merge_multi(__source.__table_);
1415    }
1416    template <class _H2, class _P2>
1417    _LIBCPP_INLINE_VISIBILITY
1418    void merge(unordered_set<key_type, _H2, _P2, allocator_type>&& __source)
1419    {
1420        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
1421                       "merging container with incompatible allocator");
1422        return __table_.__node_handle_merge_multi(__source.__table_);
1423    }
1424#endif
1425
1426    _LIBCPP_INLINE_VISIBILITY
1427    iterator erase(const_iterator __p) {return __table_.erase(__p);}
1428    _LIBCPP_INLINE_VISIBILITY
1429    size_type erase(const key_type& __k) {return __table_.__erase_multi(__k);}
1430    _LIBCPP_INLINE_VISIBILITY
1431    iterator erase(const_iterator __first, const_iterator __last)
1432        {return __table_.erase(__first, __last);}
1433    _LIBCPP_INLINE_VISIBILITY
1434    void clear() _NOEXCEPT {__table_.clear();}
1435
1436    _LIBCPP_INLINE_VISIBILITY
1437    void swap(unordered_multiset& __u)
1438        _NOEXCEPT_(__is_nothrow_swappable<__table>::value)
1439        {__table_.swap(__u.__table_);}
1440
1441    _LIBCPP_INLINE_VISIBILITY
1442    hasher hash_function() const {return __table_.hash_function();}
1443    _LIBCPP_INLINE_VISIBILITY
1444    key_equal key_eq() const {return __table_.key_eq();}
1445
1446    _LIBCPP_INLINE_VISIBILITY
1447    iterator       find(const key_type& __k)       {return __table_.find(__k);}
1448    _LIBCPP_INLINE_VISIBILITY
1449    const_iterator find(const key_type& __k) const {return __table_.find(__k);}
1450#if _LIBCPP_STD_VER > 17
1451    template<class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1452    _LIBCPP_INLINE_VISIBILITY
1453    iterator       find(const _K2& __k)            {return __table_.find(__k);}
1454    template<class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1455    _LIBCPP_INLINE_VISIBILITY
1456    const_iterator find(const _K2& __k) const      {return __table_.find(__k);}
1457#endif // _LIBCPP_STD_VER > 17
1458
1459    _LIBCPP_INLINE_VISIBILITY
1460    size_type count(const key_type& __k) const {return __table_.__count_multi(__k);}
1461#if _LIBCPP_STD_VER > 17
1462    template<class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1463    _LIBCPP_INLINE_VISIBILITY
1464    size_type count(const _K2& __k) const      {return __table_.__count_multi(__k);}
1465#endif // _LIBCPP_STD_VER > 17
1466
1467#if _LIBCPP_STD_VER > 17
1468    _LIBCPP_INLINE_VISIBILITY
1469    bool contains(const key_type& __k) const {return find(__k) != end();}
1470
1471    template<class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1472    _LIBCPP_INLINE_VISIBILITY
1473    bool contains(const _K2& __k) const      {return find(__k) != end();}
1474#endif // _LIBCPP_STD_VER > 17
1475
1476    _LIBCPP_INLINE_VISIBILITY
1477    pair<iterator, iterator>             equal_range(const key_type& __k)
1478        {return __table_.__equal_range_multi(__k);}
1479    _LIBCPP_INLINE_VISIBILITY
1480    pair<const_iterator, const_iterator> equal_range(const key_type& __k) const
1481        {return __table_.__equal_range_multi(__k);}
1482#if _LIBCPP_STD_VER > 17
1483    template<class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1484    _LIBCPP_INLINE_VISIBILITY
1485    pair<iterator, iterator>             equal_range(const _K2& __k)
1486        {return __table_.__equal_range_multi(__k);}
1487    template<class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1488    _LIBCPP_INLINE_VISIBILITY
1489    pair<const_iterator, const_iterator> equal_range(const _K2& __k) const
1490        {return __table_.__equal_range_multi(__k);}
1491#endif // _LIBCPP_STD_VER > 17
1492
1493    _LIBCPP_INLINE_VISIBILITY
1494    size_type bucket_count() const _NOEXCEPT {return __table_.bucket_count();}
1495    _LIBCPP_INLINE_VISIBILITY
1496    size_type max_bucket_count() const _NOEXCEPT {return __table_.max_bucket_count();}
1497
1498    _LIBCPP_INLINE_VISIBILITY
1499    size_type bucket_size(size_type __n) const {return __table_.bucket_size(__n);}
1500    _LIBCPP_INLINE_VISIBILITY
1501    size_type bucket(const key_type& __k) const {return __table_.bucket(__k);}
1502
1503    _LIBCPP_INLINE_VISIBILITY
1504    local_iterator       begin(size_type __n)        {return __table_.begin(__n);}
1505    _LIBCPP_INLINE_VISIBILITY
1506    local_iterator       end(size_type __n)          {return __table_.end(__n);}
1507    _LIBCPP_INLINE_VISIBILITY
1508    const_local_iterator begin(size_type __n) const  {return __table_.cbegin(__n);}
1509    _LIBCPP_INLINE_VISIBILITY
1510    const_local_iterator end(size_type __n) const    {return __table_.cend(__n);}
1511    _LIBCPP_INLINE_VISIBILITY
1512    const_local_iterator cbegin(size_type __n) const {return __table_.cbegin(__n);}
1513    _LIBCPP_INLINE_VISIBILITY
1514    const_local_iterator cend(size_type __n) const   {return __table_.cend(__n);}
1515
1516    _LIBCPP_INLINE_VISIBILITY
1517    float load_factor() const _NOEXCEPT {return __table_.load_factor();}
1518    _LIBCPP_INLINE_VISIBILITY
1519    float max_load_factor() const _NOEXCEPT {return __table_.max_load_factor();}
1520    _LIBCPP_INLINE_VISIBILITY
1521    void max_load_factor(float __mlf) {__table_.max_load_factor(__mlf);}
1522    _LIBCPP_INLINE_VISIBILITY
1523    void rehash(size_type __n) {__table_.rehash(__n);}
1524    _LIBCPP_INLINE_VISIBILITY
1525    void reserve(size_type __n) {__table_.reserve(__n);}
1526
1527#if _LIBCPP_DEBUG_LEVEL == 2
1528
1529    bool __dereferenceable(const const_iterator* __i) const
1530        {return __table_.__dereferenceable(__i);}
1531    bool __decrementable(const const_iterator* __i) const
1532        {return __table_.__decrementable(__i);}
1533    bool __addable(const const_iterator* __i, ptrdiff_t __n) const
1534        {return __table_.__addable(__i, __n);}
1535    bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const
1536        {return __table_.__addable(__i, __n);}
1537
1538#endif // _LIBCPP_DEBUG_LEVEL == 2
1539
1540};
1541
1542#if _LIBCPP_STD_VER >= 17
1543template<class _InputIterator,
1544         class _Hash = hash<__iter_value_type<_InputIterator>>,
1545         class _Pred = equal_to<__iter_value_type<_InputIterator>>,
1546         class _Allocator = allocator<__iter_value_type<_InputIterator>>,
1547         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
1548         class = enable_if_t<!__is_allocator<_Hash>::value>,
1549         class = enable_if_t<!is_integral<_Hash>::value>,
1550         class = enable_if_t<!__is_allocator<_Pred>::value>,
1551         class = enable_if_t<__is_allocator<_Allocator>::value>>
1552unordered_multiset(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type = 0,
1553              _Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator())
1554  -> unordered_multiset<__iter_value_type<_InputIterator>, _Hash, _Pred, _Allocator>;
1555
1556template<class _Tp, class _Hash = hash<_Tp>,
1557         class _Pred = equal_to<_Tp>, class _Allocator = allocator<_Tp>,
1558         class = enable_if_t<!__is_allocator<_Hash>::value>,
1559         class = enable_if_t<!is_integral<_Hash>::value>,
1560         class = enable_if_t<!__is_allocator<_Pred>::value>,
1561         class = enable_if_t<__is_allocator<_Allocator>::value>>
1562unordered_multiset(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type = 0,
1563              _Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator())
1564  -> unordered_multiset<_Tp, _Hash, _Pred, _Allocator>;
1565
1566template<class _InputIterator, class _Allocator,
1567         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
1568         class = enable_if_t<__is_allocator<_Allocator>::value>>
1569unordered_multiset(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type, _Allocator)
1570  -> unordered_multiset<__iter_value_type<_InputIterator>,
1571                   hash<__iter_value_type<_InputIterator>>,
1572                   equal_to<__iter_value_type<_InputIterator>>,
1573                   _Allocator>;
1574
1575template<class _InputIterator, class _Hash, class _Allocator,
1576         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
1577         class = enable_if_t<!__is_allocator<_Hash>::value>,
1578         class = enable_if_t<!is_integral<_Hash>::value>,
1579         class = enable_if_t<__is_allocator<_Allocator>::value>>
1580unordered_multiset(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type,
1581              _Hash, _Allocator)
1582  -> unordered_multiset<__iter_value_type<_InputIterator>, _Hash,
1583                   equal_to<__iter_value_type<_InputIterator>>,
1584                   _Allocator>;
1585
1586template<class _Tp, class _Allocator,
1587         class = enable_if_t<__is_allocator<_Allocator>::value>>
1588unordered_multiset(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type, _Allocator)
1589  -> unordered_multiset<_Tp, hash<_Tp>, equal_to<_Tp>, _Allocator>;
1590
1591template<class _Tp, class _Hash, class _Allocator,
1592         class = enable_if_t<!__is_allocator<_Hash>::value>,
1593         class = enable_if_t<!is_integral<_Hash>::value>,
1594         class = enable_if_t<__is_allocator<_Allocator>::value>>
1595unordered_multiset(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
1596  -> unordered_multiset<_Tp, _Hash, equal_to<_Tp>, _Allocator>;
1597#endif
1598
1599template <class _Value, class _Hash, class _Pred, class _Alloc>
1600unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1601        size_type __n, const hasher& __hf, const key_equal& __eql)
1602    : __table_(__hf, __eql)
1603{
1604#if _LIBCPP_DEBUG_LEVEL == 2
1605    __get_db()->__insert_c(this);
1606#endif
1607    __table_.rehash(__n);
1608}
1609
1610template <class _Value, class _Hash, class _Pred, class _Alloc>
1611unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1612        size_type __n, const hasher& __hf, const key_equal& __eql,
1613        const allocator_type& __a)
1614    : __table_(__hf, __eql, __a)
1615{
1616#if _LIBCPP_DEBUG_LEVEL == 2
1617    __get_db()->__insert_c(this);
1618#endif
1619    __table_.rehash(__n);
1620}
1621
1622template <class _Value, class _Hash, class _Pred, class _Alloc>
1623template <class _InputIterator>
1624unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1625        _InputIterator __first, _InputIterator __last)
1626{
1627#if _LIBCPP_DEBUG_LEVEL == 2
1628    __get_db()->__insert_c(this);
1629#endif
1630    insert(__first, __last);
1631}
1632
1633template <class _Value, class _Hash, class _Pred, class _Alloc>
1634template <class _InputIterator>
1635unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1636        _InputIterator __first, _InputIterator __last, size_type __n,
1637        const hasher& __hf, const key_equal& __eql)
1638    : __table_(__hf, __eql)
1639{
1640#if _LIBCPP_DEBUG_LEVEL == 2
1641    __get_db()->__insert_c(this);
1642#endif
1643    __table_.rehash(__n);
1644    insert(__first, __last);
1645}
1646
1647template <class _Value, class _Hash, class _Pred, class _Alloc>
1648template <class _InputIterator>
1649unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1650        _InputIterator __first, _InputIterator __last, size_type __n,
1651        const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
1652    : __table_(__hf, __eql, __a)
1653{
1654#if _LIBCPP_DEBUG_LEVEL == 2
1655    __get_db()->__insert_c(this);
1656#endif
1657    __table_.rehash(__n);
1658    insert(__first, __last);
1659}
1660
1661template <class _Value, class _Hash, class _Pred, class _Alloc>
1662inline
1663unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1664        const allocator_type& __a)
1665    : __table_(__a)
1666{
1667#if _LIBCPP_DEBUG_LEVEL == 2
1668    __get_db()->__insert_c(this);
1669#endif
1670}
1671
1672template <class _Value, class _Hash, class _Pred, class _Alloc>
1673unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1674        const unordered_multiset& __u)
1675    : __table_(__u.__table_)
1676{
1677#if _LIBCPP_DEBUG_LEVEL == 2
1678    __get_db()->__insert_c(this);
1679#endif
1680    __table_.rehash(__u.bucket_count());
1681    insert(__u.begin(), __u.end());
1682}
1683
1684template <class _Value, class _Hash, class _Pred, class _Alloc>
1685unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1686        const unordered_multiset& __u, const allocator_type& __a)
1687    : __table_(__u.__table_, __a)
1688{
1689#if _LIBCPP_DEBUG_LEVEL == 2
1690    __get_db()->__insert_c(this);
1691#endif
1692    __table_.rehash(__u.bucket_count());
1693    insert(__u.begin(), __u.end());
1694}
1695
1696#ifndef _LIBCPP_CXX03_LANG
1697
1698template <class _Value, class _Hash, class _Pred, class _Alloc>
1699inline
1700unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1701        unordered_multiset&& __u)
1702    _NOEXCEPT_(is_nothrow_move_constructible<__table>::value)
1703    : __table_(_VSTD::move(__u.__table_))
1704{
1705#if _LIBCPP_DEBUG_LEVEL == 2
1706    __get_db()->__insert_c(this);
1707    __get_db()->swap(this, &__u);
1708#endif
1709}
1710
1711template <class _Value, class _Hash, class _Pred, class _Alloc>
1712unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1713        unordered_multiset&& __u, const allocator_type& __a)
1714    : __table_(_VSTD::move(__u.__table_), __a)
1715{
1716#if _LIBCPP_DEBUG_LEVEL == 2
1717    __get_db()->__insert_c(this);
1718#endif
1719    if (__a != __u.get_allocator())
1720    {
1721        iterator __i = __u.begin();
1722        while (__u.size() != 0)
1723            __table_.__insert_multi(_VSTD::move(__u.__table_.remove(__i++)->__value_));
1724    }
1725#if _LIBCPP_DEBUG_LEVEL == 2
1726    else
1727        __get_db()->swap(this, &__u);
1728#endif
1729}
1730
1731template <class _Value, class _Hash, class _Pred, class _Alloc>
1732unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1733        initializer_list<value_type> __il)
1734{
1735#if _LIBCPP_DEBUG_LEVEL == 2
1736    __get_db()->__insert_c(this);
1737#endif
1738    insert(__il.begin(), __il.end());
1739}
1740
1741template <class _Value, class _Hash, class _Pred, class _Alloc>
1742unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1743        initializer_list<value_type> __il, size_type __n, const hasher& __hf,
1744        const key_equal& __eql)
1745    : __table_(__hf, __eql)
1746{
1747#if _LIBCPP_DEBUG_LEVEL == 2
1748    __get_db()->__insert_c(this);
1749#endif
1750    __table_.rehash(__n);
1751    insert(__il.begin(), __il.end());
1752}
1753
1754template <class _Value, class _Hash, class _Pred, class _Alloc>
1755unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1756        initializer_list<value_type> __il, size_type __n, const hasher& __hf,
1757        const key_equal& __eql, const allocator_type& __a)
1758    : __table_(__hf, __eql, __a)
1759{
1760#if _LIBCPP_DEBUG_LEVEL == 2
1761    __get_db()->__insert_c(this);
1762#endif
1763    __table_.rehash(__n);
1764    insert(__il.begin(), __il.end());
1765}
1766
1767template <class _Value, class _Hash, class _Pred, class _Alloc>
1768inline
1769unordered_multiset<_Value, _Hash, _Pred, _Alloc>&
1770unordered_multiset<_Value, _Hash, _Pred, _Alloc>::operator=(
1771        unordered_multiset&& __u)
1772    _NOEXCEPT_(is_nothrow_move_assignable<__table>::value)
1773{
1774    __table_ = _VSTD::move(__u.__table_);
1775    return *this;
1776}
1777
1778template <class _Value, class _Hash, class _Pred, class _Alloc>
1779inline
1780unordered_multiset<_Value, _Hash, _Pred, _Alloc>&
1781unordered_multiset<_Value, _Hash, _Pred, _Alloc>::operator=(
1782        initializer_list<value_type> __il)
1783{
1784    __table_.__assign_multi(__il.begin(), __il.end());
1785    return *this;
1786}
1787
1788#endif // _LIBCPP_CXX03_LANG
1789
1790template <class _Value, class _Hash, class _Pred, class _Alloc>
1791template <class _InputIterator>
1792inline
1793void
1794unordered_multiset<_Value, _Hash, _Pred, _Alloc>::insert(_InputIterator __first,
1795                                                         _InputIterator __last)
1796{
1797    for (; __first != __last; ++__first)
1798        __table_.__insert_multi(*__first);
1799}
1800
1801template <class _Value, class _Hash, class _Pred, class _Alloc>
1802inline _LIBCPP_INLINE_VISIBILITY
1803void
1804swap(unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __x,
1805     unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __y)
1806    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
1807{
1808    __x.swap(__y);
1809}
1810
1811#if _LIBCPP_STD_VER > 17
1812template <class _Value, class _Hash, class _Pred, class _Alloc,
1813          class _Predicate>
1814inline _LIBCPP_INLINE_VISIBILITY
1815    typename unordered_multiset<_Value, _Hash, _Pred, _Alloc>::size_type
1816    erase_if(unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __c,
1817             _Predicate __pred) {
1818  return _VSTD::__libcpp_erase_if_container(__c, __pred);
1819}
1820#endif
1821
1822template <class _Value, class _Hash, class _Pred, class _Alloc>
1823bool
1824operator==(const unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __x,
1825           const unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __y)
1826{
1827    if (__x.size() != __y.size())
1828        return false;
1829    typedef typename unordered_multiset<_Value, _Hash, _Pred, _Alloc>::const_iterator
1830                                                                 const_iterator;
1831    typedef pair<const_iterator, const_iterator> _EqRng;
1832    for (const_iterator __i = __x.begin(), __ex = __x.end(); __i != __ex;)
1833    {
1834        _EqRng __xeq = __x.equal_range(*__i);
1835        _EqRng __yeq = __y.equal_range(*__i);
1836        if (_VSTD::distance(__xeq.first, __xeq.second) !=
1837            _VSTD::distance(__yeq.first, __yeq.second) ||
1838                  !_VSTD::is_permutation(__xeq.first, __xeq.second, __yeq.first))
1839            return false;
1840        __i = __xeq.second;
1841    }
1842    return true;
1843}
1844
1845template <class _Value, class _Hash, class _Pred, class _Alloc>
1846inline _LIBCPP_INLINE_VISIBILITY
1847bool
1848operator!=(const unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __x,
1849           const unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __y)
1850{
1851    return !(__x == __y);
1852}
1853
1854_LIBCPP_END_NAMESPACE_STD
1855
1856#endif // _LIBCPP_UNORDERED_SET
1857