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-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef _LIBCPP___ALGORITHM_BINARY_SEARCH_H
10 #define _LIBCPP___ALGORITHM_BINARY_SEARCH_H
11 
12 #include <__algorithm/comp.h>
13 #include <__algorithm/comp_ref_type.h>
14 #include <__algorithm/lower_bound.h>
15 #include <__config>
16 #include <__iterator/iterator_traits.h>
17 
18 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
19 #  pragma GCC system_header
20 #endif
21 
22 _LIBCPP_BEGIN_NAMESPACE_STD
23 
24 template <class _ForwardIterator, class _Tp, class _Compare>
25 _LIBCPP_NODISCARD_EXT inline
26 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
27 bool
28 binary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value, _Compare __comp)
29 {
30     using _Comp_ref = typename __comp_ref_type<_Compare>::type;
31     __first = std::lower_bound<_ForwardIterator, _Tp, _Comp_ref>(__first, __last, __value, __comp);
32     return __first != __last && !__comp(__value, *__first);
33 }
34 
35 template <class _ForwardIterator, class _Tp>
36 _LIBCPP_NODISCARD_EXT inline
37 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
38 bool
39 binary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value)
40 {
41     return std::binary_search(__first, __last, __value,
42                               __less<typename iterator_traits<_ForwardIterator>::value_type, _Tp>());
43 }
44 
45 _LIBCPP_END_NAMESPACE_STD
46 
47 #endif // _LIBCPP___ALGORITHM_BINARY_SEARCH_H
48