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_UNIQUE_H
10#define _LIBCPP___ALGORITHM_UNIQUE_H
11
12#include <__algorithm/adjacent_find.h>
13#include <__algorithm/comp.h>
14#include <__algorithm/iterator_operations.h>
15#include <__config>
16#include <__functional/identity.h>
17#include <__iterator/iterator_traits.h>
18#include <__utility/move.h>
19#include <__utility/pair.h>
20
21#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
22# pragma GCC system_header
23#endif
24
25_LIBCPP_PUSH_MACROS
26#include <__undef_macros>
27
28_LIBCPP_BEGIN_NAMESPACE_STD
29
30// unique
31
32template <class _AlgPolicy, class _Iter, class _Sent, class _BinaryPredicate>
33[[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 std::pair<_Iter, _Iter>
34__unique(_Iter __first, _Sent __last, _BinaryPredicate&& __pred) {
35 __identity __proj;
36 __first = std::__adjacent_find(__first, __last, __pred, __proj);
37 if (__first != __last) {
38 // ... a a ? ...
39 // f i
40 _Iter __i = __first;
41 for (++__i; ++__i != __last;)
42 if (!__pred(*__first, *__i))
43 *++__first = _IterOps<_AlgPolicy>::__iter_move(__i);
44 ++__first;
45 return std::pair<_Iter, _Iter>(std::move(__first), std::move(__i));
46 }
47 return std::pair<_Iter, _Iter>(__first, __first);
48}
49
50template <class _ForwardIterator, class _BinaryPredicate>
51[[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
52unique(_ForwardIterator __first, _ForwardIterator __last, _BinaryPredicate __pred) {
53 return std::__unique<_ClassicAlgPolicy>(std::move(__first), std::move(__last), __pred).first;
54}
55
56template <class _ForwardIterator>
57[[__nodiscard__]] inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
58unique(_ForwardIterator __first, _ForwardIterator __last) {
59 return std::unique(__first, __last, __equal_to());
60}
61
62_LIBCPP_END_NAMESPACE_STD
63
64_LIBCPP_POP_MACROS
65
66#endif // _LIBCPP___ALGORITHM_UNIQUE_H
67