1e78f53d1SNikolas Klauser //===----------------------------------------------------------------------===// 2e78f53d1SNikolas Klauser // 3e78f53d1SNikolas Klauser // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4e78f53d1SNikolas Klauser // See https://llvm.org/LICENSE.txt for license information. 5e78f53d1SNikolas Klauser // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6e78f53d1SNikolas Klauser // 7e78f53d1SNikolas Klauser //===----------------------------------------------------------------------===// 8e78f53d1SNikolas Klauser 9*ce777190SNikolas Klauser #ifndef _LIBCPP___CXX03___ALGORITHM_PARTITION_POINT_H 10*ce777190SNikolas Klauser #define _LIBCPP___CXX03___ALGORITHM_PARTITION_POINT_H 11e78f53d1SNikolas Klauser 1273fbae83SNikolas Klauser #include <__cxx03/__algorithm/half_positive.h> 1373fbae83SNikolas Klauser #include <__cxx03/__config> 1473fbae83SNikolas Klauser #include <__cxx03/__iterator/advance.h> 1573fbae83SNikolas Klauser #include <__cxx03/__iterator/distance.h> 1673fbae83SNikolas Klauser #include <__cxx03/__iterator/iterator_traits.h> 17e78f53d1SNikolas Klauser 18e78f53d1SNikolas Klauser #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 19e78f53d1SNikolas Klauser # pragma GCC system_header 20e78f53d1SNikolas Klauser #endif 21e78f53d1SNikolas Klauser 22e78f53d1SNikolas Klauser _LIBCPP_BEGIN_NAMESPACE_STD 23e78f53d1SNikolas Klauser 24e78f53d1SNikolas Klauser template <class _ForwardIterator, class _Predicate> 25e78f53d1SNikolas Klauser _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator 26e78f53d1SNikolas Klauser partition_point(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) { 27e78f53d1SNikolas Klauser typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type; 28e78f53d1SNikolas Klauser difference_type __len = std::distance(__first, __last); 29e78f53d1SNikolas Klauser while (__len != 0) { 30e78f53d1SNikolas Klauser difference_type __l2 = std::__half_positive(__len); 31e78f53d1SNikolas Klauser _ForwardIterator __m = __first; 32e78f53d1SNikolas Klauser std::advance(__m, __l2); 33e78f53d1SNikolas Klauser if (__pred(*__m)) { 34e78f53d1SNikolas Klauser __first = ++__m; 35e78f53d1SNikolas Klauser __len -= __l2 + 1; 36e78f53d1SNikolas Klauser } else 37e78f53d1SNikolas Klauser __len = __l2; 38e78f53d1SNikolas Klauser } 39e78f53d1SNikolas Klauser return __first; 40e78f53d1SNikolas Klauser } 41e78f53d1SNikolas Klauser 42e78f53d1SNikolas Klauser _LIBCPP_END_NAMESPACE_STD 43e78f53d1SNikolas Klauser 44*ce777190SNikolas Klauser #endif // _LIBCPP___CXX03___ALGORITHM_PARTITION_POINT_H 45