libcxx/include/__algorithm/count_if.h
2023-10-03 17:20:52 -07:00

36 lines
1.1 KiB
C++

// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP___ALGORITHM_COUNT_IF_H
#define _LIBCPP___ALGORITHM_COUNT_IF_H
#include <__config>
#include <__iterator/iterator_traits.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
template <class _InputIterator, class _Predicate>
_LIBCPP_NODISCARD_EXT inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20
typename iterator_traits<_InputIterator>::difference_type
count_if(_InputIterator __first, _InputIterator __last, _Predicate __pred) {
typename iterator_traits<_InputIterator>::difference_type __r(0);
for (; __first != __last; ++__first)
if (__pred(*__first))
++__r;
return __r;
}
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP___ALGORITHM_COUNT_IF_H