xref: /freebsd-src/contrib/llvm-project/libcxx/include/__algorithm/count_if.h (revision 0fca6ea1d4eea4c934cfff25ac9ee8ad6fe95583)
1fe6060f1SDimitry Andric // -*- C++ -*-
2fe6060f1SDimitry Andric //===----------------------------------------------------------------------===//
3fe6060f1SDimitry Andric //
4fe6060f1SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5fe6060f1SDimitry Andric // See https://llvm.org/LICENSE.txt for license information.
6fe6060f1SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7fe6060f1SDimitry Andric //
8fe6060f1SDimitry Andric //===----------------------------------------------------------------------===//
9fe6060f1SDimitry Andric 
10fe6060f1SDimitry Andric #ifndef _LIBCPP___ALGORITHM_COUNT_IF_H
11fe6060f1SDimitry Andric #define _LIBCPP___ALGORITHM_COUNT_IF_H
12fe6060f1SDimitry Andric 
13fe6060f1SDimitry Andric #include <__config>
14fe6060f1SDimitry Andric #include <__iterator/iterator_traits.h>
15fe6060f1SDimitry Andric 
16fe6060f1SDimitry Andric #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
17fe6060f1SDimitry Andric #  pragma GCC system_header
18fe6060f1SDimitry Andric #endif
19fe6060f1SDimitry Andric 
20fe6060f1SDimitry Andric _LIBCPP_BEGIN_NAMESPACE_STD
21fe6060f1SDimitry Andric 
22fe6060f1SDimitry Andric template <class _InputIterator, class _Predicate>
23*0fca6ea1SDimitry Andric _LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
24fe6060f1SDimitry Andric typename iterator_traits<_InputIterator>::difference_type
25fe6060f1SDimitry Andric count_if(_InputIterator __first, _InputIterator __last, _Predicate __pred) {
26fe6060f1SDimitry Andric   typename iterator_traits<_InputIterator>::difference_type __r(0);
27fe6060f1SDimitry Andric   for (; __first != __last; ++__first)
28fe6060f1SDimitry Andric     if (__pred(*__first))
29fe6060f1SDimitry Andric       ++__r;
30fe6060f1SDimitry Andric   return __r;
31fe6060f1SDimitry Andric }
32fe6060f1SDimitry Andric 
33fe6060f1SDimitry Andric _LIBCPP_END_NAMESPACE_STD
34fe6060f1SDimitry Andric 
35fe6060f1SDimitry Andric #endif // _LIBCPP___ALGORITHM_COUNT_IF_H
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