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1// -*- C++ -*-2//===----------------------------------------------------------------------===//3//4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.5// See https://llvm.org/LICENSE.txt for license information.6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception7//8//===----------------------------------------------------------------------===//9 10#ifndef _LIBCPP___ALGORITHM_COUNT_IF_H11#define _LIBCPP___ALGORITHM_COUNT_IF_H12 13#include <__algorithm/iterator_operations.h>14#include <__config>15#include <__functional/identity.h>16#include <__iterator/iterator_traits.h>17#include <__type_traits/invoke.h>18 19#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)20# pragma GCC system_header21#endif22 23_LIBCPP_BEGIN_NAMESPACE_STD24 25template <class _AlgPolicy, class _Iter, class _Sent, class _Proj, class _Pred>26_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __policy_iter_diff_t<_AlgPolicy, _Iter>27__count_if(_Iter __first, _Sent __last, _Pred& __pred, _Proj& __proj) {28 __policy_iter_diff_t<_AlgPolicy, _Iter> __counter(0);29 for (; __first != __last; ++__first) {30 if (std::__invoke(__pred, std::__invoke(__proj, *__first)))31 ++__counter;32 }33 return __counter;34}35 36template <class _InputIterator, class _Predicate>37[[__nodiscard__]] inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX2038typename iterator_traits<_InputIterator>::difference_type39count_if(_InputIterator __first, _InputIterator __last, _Predicate __pred) {40 __identity __proj;41 return std::__count_if<_ClassicAlgPolicy>(__first, __last, __pred, __proj);42}43 44_LIBCPP_END_NAMESPACE_STD45 46#endif // _LIBCPP___ALGORITHM_COUNT_IF_H47