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 <__algorithm/comp.h> 14 #include <__iterator/iterator_traits.h> 15 16 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 17 #pragma GCC system_header 18 #endif 19 20 _LIBCPP_PUSH_MACROS 21 #include <__undef_macros> 22 23 _LIBCPP_BEGIN_NAMESPACE_STD 24 25 template <class _RandomAccessIterator, class _Compare> 26 _LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _RandomAccessIterator 27 is_heap_until(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp) 28 { 29 typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type; 30 difference_type __len = __last - __first; 31 difference_type __p = 0; 32 difference_type __c = 1; 33 _RandomAccessIterator __pp = __first; 34 while (__c < __len) 35 { 36 _RandomAccessIterator __cp = __first + __c; 37 if (__comp(*__pp, *__cp)) 38 return __cp; 39 ++__c; 40 ++__cp; 41 if (__c == __len) 42 return __last; 43 if (__comp(*__pp, *__cp)) 44 return __cp; 45 ++__p; 46 ++__pp; 47 __c = 2 * __p + 1; 48 } 49 return __last; 50 } 51 52 template<class _RandomAccessIterator> 53 _LIBCPP_NODISCARD_EXT inline 54 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 55 _RandomAccessIterator 56 is_heap_until(_RandomAccessIterator __first, _RandomAccessIterator __last) 57 { 58 return _VSTD::is_heap_until(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>()); 59 } 60 61 _LIBCPP_END_NAMESPACE_STD 62 63 _LIBCPP_POP_MACROS 64 65 #endif // _LIBCPP___ALGORITHM_IS_HEAP_UNTIL_H 66