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_POP_HEAP_H 10 #define _LIBCPP___ALGORITHM_POP_HEAP_H 11 12 #include <__algorithm/comp.h> 13 #include <__algorithm/comp_ref_type.h> 14 #include <__algorithm/push_heap.h> 15 #include <__algorithm/sift_down.h> 16 #include <__config> 17 #include <__iterator/iterator_traits.h> 18 #include <__utility/move.h> 19 20 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 21 # pragma GCC system_header 22 #endif 23 24 _LIBCPP_BEGIN_NAMESPACE_STD 25 26 template <class _Compare, class _RandomAccessIterator> 27 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 28 void 29 __pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp, 30 typename iterator_traits<_RandomAccessIterator>::difference_type __len) 31 { 32 using value_type = typename iterator_traits<_RandomAccessIterator>::value_type; 33 34 if (__len > 1) 35 { 36 value_type __top = std::move(*__first); // create a hole at __first 37 _RandomAccessIterator __hole = std::__floyd_sift_down<_Compare>(__first, __comp, __len); 38 --__last; 39 if (__hole == __last) { 40 *__hole = std::move(__top); 41 } else { 42 *__hole = std::move(*__last); 43 ++__hole; 44 *__last = std::move(__top); 45 std::__sift_up<_Compare>(__first, __hole, __comp, __hole - __first); 46 } 47 } 48 } 49 50 template <class _RandomAccessIterator, class _Compare> 51 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 52 void 53 pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp) 54 { 55 typedef typename __comp_ref_type<_Compare>::type _Comp_ref; 56 _VSTD::__pop_heap<_Comp_ref>(__first, __last, __comp, __last - __first); 57 } 58 59 template <class _RandomAccessIterator> 60 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 61 void 62 pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last) 63 { 64 _VSTD::pop_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>()); 65 } 66 67 _LIBCPP_END_NAMESPACE_STD 68 69 #endif // _LIBCPP___ALGORITHM_POP_HEAP_H 70