1 //===----------------------------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef _LIBCPP___ALGORITHM_PUSH_HEAP_H 10 #define _LIBCPP___ALGORITHM_PUSH_HEAP_H 11 12 #include <__algorithm/comp.h> 13 #include <__algorithm/comp_ref_type.h> 14 #include <__algorithm/iterator_operations.h> 15 #include <__config> 16 #include <__iterator/iterator_traits.h> 17 #include <__type_traits/is_assignable.h> 18 #include <__type_traits/is_constructible.h> 19 #include <__utility/move.h> 20 21 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 22 # pragma GCC system_header 23 #endif 24 25 _LIBCPP_PUSH_MACROS 26 #include <__undef_macros> 27 28 _LIBCPP_BEGIN_NAMESPACE_STD 29 30 template <class _AlgPolicy, class _Compare, class _RandomAccessIterator> 31 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void 32 __sift_up(_RandomAccessIterator __first, 33 _RandomAccessIterator __last, 34 _Compare&& __comp, 35 typename iterator_traits<_RandomAccessIterator>::difference_type __len) { 36 using value_type = typename iterator_traits<_RandomAccessIterator>::value_type; 37 38 if (__len > 1) { 39 __len = (__len - 2) / 2; 40 _RandomAccessIterator __ptr = __first + __len; 41 42 if (__comp(*__ptr, *--__last)) { 43 value_type __t(_IterOps<_AlgPolicy>::__iter_move(__last)); 44 do { 45 *__last = _IterOps<_AlgPolicy>::__iter_move(__ptr); 46 __last = __ptr; 47 if (__len == 0) 48 break; 49 __len = (__len - 1) / 2; 50 __ptr = __first + __len; 51 } while (__comp(*__ptr, __t)); 52 53 *__last = std::move(__t); 54 } 55 } 56 } 57 58 template <class _AlgPolicy, class _RandomAccessIterator, class _Compare> 59 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void 60 __push_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare& __comp) { 61 typename iterator_traits<_RandomAccessIterator>::difference_type __len = __last - __first; 62 std::__sift_up<_AlgPolicy, __comp_ref_type<_Compare> >(std::move(__first), std::move(__last), __comp, __len); 63 } 64 65 template <class _RandomAccessIterator, class _Compare> 66 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void 67 push_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp) { 68 static_assert(std::is_copy_constructible<_RandomAccessIterator>::value, "Iterators must be copy constructible."); 69 static_assert(std::is_copy_assignable<_RandomAccessIterator>::value, "Iterators must be copy assignable."); 70 71 std::__push_heap<_ClassicAlgPolicy>(std::move(__first), std::move(__last), __comp); 72 } 73 74 template <class _RandomAccessIterator> 75 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void 76 push_heap(_RandomAccessIterator __first, _RandomAccessIterator __last) { 77 std::push_heap(std::move(__first), std::move(__last), __less<>()); 78 } 79 80 _LIBCPP_END_NAMESPACE_STD 81 82 _LIBCPP_POP_MACROS 83 84 #endif // _LIBCPP___ALGORITHM_PUSH_HEAP_H 85