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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-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef _LIBCPP___ALGORITHM_PARTITION_POINT_H10#define _LIBCPP___ALGORITHM_PARTITION_POINT_H11 12#include <__algorithm/half_positive.h>13#include <__config>14#include <__iterator/advance.h>15#include <__iterator/distance.h>16#include <__iterator/iterator_traits.h>17 18#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)19# pragma GCC system_header20#endif21 22_LIBCPP_BEGIN_NAMESPACE_STD23 24template <class _ForwardIterator, class _Predicate>25_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator26partition_point(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) {27 typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;28 difference_type __len = std::distance(__first, __last);29 while (__len != 0) {30 difference_type __l2 = std::__half_positive(__len);31 _ForwardIterator __m = __first;32 std::advance(__m, __l2);33 if (__pred(*__m)) {34 __first = ++__m;35 __len -= __l2 + 1;36 } else37 __len = __l2;38 }39 return __first;40}41 42_LIBCPP_END_NAMESPACE_STD43 44#endif // _LIBCPP___ALGORITHM_PARTITION_POINT_H45