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-exception
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #ifndef _LIBCPP___ALGORITHM_ADJACENT_FIND_H
11 #define _LIBCPP___ALGORITHM_ADJACENT_FIND_H
12 
13 #include <__config>
14 #include <__algorithm/comp.h>
15 #include <__iterator/iterator_traits.h>
16 
17 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
18 #pragma GCC system_header
19 #endif
20 
21 _LIBCPP_PUSH_MACROS
22 #include <__undef_macros>
23 
24 _LIBCPP_BEGIN_NAMESPACE_STD
25 
26 template <class _ForwardIterator, class _BinaryPredicate>
27 _LIBCPP_NODISCARD_EXT inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
28 adjacent_find(_ForwardIterator __first, _ForwardIterator __last, _BinaryPredicate __pred) {
29   if (__first != __last) {
30     _ForwardIterator __i = __first;
31     while (++__i != __last) {
32       if (__pred(*__first, *__i))
33         return __first;
34       __first = __i;
35     }
36   }
37   return __last;
38 }
39 
40 template <class _ForwardIterator>
41 _LIBCPP_NODISCARD_EXT inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
42 adjacent_find(_ForwardIterator __first, _ForwardIterator __last) {
43   typedef typename iterator_traits<_ForwardIterator>::value_type __v;
44   return _VSTD::adjacent_find(__first, __last, __equal_to<__v>());
45 }
46 
47 _LIBCPP_END_NAMESPACE_STD
48 
49 _LIBCPP_POP_MACROS
50 
51 #endif // _LIBCPP___ALGORITHM_ADJACENT_FIND_H
52