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_IS_HEAP_UNTIL_H 10 #define _LIBCPP___ALGORITHM_IS_HEAP_UNTIL_H 11 12 #include <__config> 13 #include <__iterator/iterator_traits.h> 14 15 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 16 #pragma GCC system_header 17 #endif 18 19 _LIBCPP_PUSH_MACROS 20 #include <__undef_macros> 21 22 _LIBCPP_BEGIN_NAMESPACE_STD 23 24 template <class _RandomAccessIterator, class _Compare> 25 _LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _RandomAccessIterator 26 is_heap_until(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp) 27 { 28 typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type; 29 difference_type __len = __last - __first; 30 difference_type __p = 0; 31 difference_type __c = 1; 32 _RandomAccessIterator __pp = __first; 33 while (__c < __len) 34 { 35 _RandomAccessIterator __cp = __first + __c; 36 if (__comp(*__pp, *__cp)) 37 return __cp; 38 ++__c; 39 ++__cp; 40 if (__c == __len) 41 return __last; 42 if (__comp(*__pp, *__cp)) 43 return __cp; 44 ++__p; 45 ++__pp; 46 __c = 2 * __p + 1; 47 } 48 return __last; 49 } 50 51 template<class _RandomAccessIterator> 52 _LIBCPP_NODISCARD_EXT inline 53 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 54 _RandomAccessIterator 55 is_heap_until(_RandomAccessIterator __first, _RandomAccessIterator __last) 56 { 57 return _VSTD::is_heap_until(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>()); 58 } 59 60 _LIBCPP_END_NAMESPACE_STD 61 62 _LIBCPP_POP_MACROS 63 64 #endif // _LIBCPP___ALGORITHM_IS_HEAP_UNTIL_H 65