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 <__assert> 17 #include <__config> 18 #include <__iterator/iterator_traits.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_BEGIN_NAMESPACE_STD 26 27 template <class _Compare, class _RandomAccessIterator> 28 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 29 void __pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare& __comp, 30 typename iterator_traits<_RandomAccessIterator>::difference_type __len) { 31 _LIBCPP_ASSERT(__len > 0, "The heap given to pop_heap must be non-empty"); 32 33 using _CompRef = typename __comp_ref_type<_Compare>::type; 34 _CompRef __comp_ref = __comp; 35 36 using value_type = typename iterator_traits<_RandomAccessIterator>::value_type; 37 if (__len > 1) { 38 value_type __top = std::move(*__first); // create a hole at __first 39 _RandomAccessIterator __hole = std::__floyd_sift_down<_CompRef>(__first, __comp_ref, __len); 40 --__last; 41 42 if (__hole == __last) { 43 *__hole = std::move(__top); 44 } else { 45 *__hole = std::move(*__last); 46 ++__hole; 47 *__last = std::move(__top); 48 std::__sift_up<_CompRef>(__first, __hole, __comp_ref, __hole - __first); 49 } 50 } 51 } 52 53 template <class _RandomAccessIterator, class _Compare> 54 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX17 55 void pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp) { 56 typename iterator_traits<_RandomAccessIterator>::difference_type __len = __last - __first; 57 std::__pop_heap(std::move(__first), std::move(__last), __comp, __len); 58 } 59 60 template <class _RandomAccessIterator> 61 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX17 62 void pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last) { 63 std::pop_heap(std::move(__first), std::move(__last), 64 __less<typename iterator_traits<_RandomAccessIterator>::value_type>()); 65 } 66 67 _LIBCPP_END_NAMESPACE_STD 68 69 #endif // _LIBCPP___ALGORITHM_POP_HEAP_H 70