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_SET_INTERSECTION_H
10 #define _LIBCPP___ALGORITHM_SET_INTERSECTION_H
11
12 #include <__algorithm/comp.h>
13 #include <__algorithm/comp_ref_type.h>
14 #include <__algorithm/iterator_operations.h>
15 #include <__config>
16 #include <__iterator/iterator_traits.h>
17 #include <__iterator/next.h>
18 #include <__utility/move.h>
19
20 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
21 # pragma GCC system_header
22 #endif
23
24 _LIBCPP_BEGIN_NAMESPACE_STD
25
26 template <class _InIter1, class _InIter2, class _OutIter>
27 struct __set_intersection_result {
28 _InIter1 __in1_;
29 _InIter2 __in2_;
30 _OutIter __out_;
31
32 // need a constructor as C++03 aggregate init is hard
33 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
__set_intersection_result__set_intersection_result34 __set_intersection_result(_InIter1&& __in_iter1, _InIter2&& __in_iter2, _OutIter&& __out_iter)
35 : __in1_(std::move(__in_iter1)), __in2_(std::move(__in_iter2)), __out_(std::move(__out_iter)) {}
36 };
37
38 template <class _AlgPolicy, class _Compare, class _InIter1, class _Sent1, class _InIter2, class _Sent2, class _OutIter>
39 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __set_intersection_result<_InIter1, _InIter2, _OutIter>
__set_intersection(_InIter1 __first1,_Sent1 __last1,_InIter2 __first2,_Sent2 __last2,_OutIter __result,_Compare && __comp)40 __set_intersection(
41 _InIter1 __first1, _Sent1 __last1, _InIter2 __first2, _Sent2 __last2, _OutIter __result, _Compare&& __comp) {
42 while (__first1 != __last1 && __first2 != __last2) {
43 if (__comp(*__first1, *__first2))
44 ++__first1;
45 else {
46 if (!__comp(*__first2, *__first1)) {
47 *__result = *__first1;
48 ++__result;
49 ++__first1;
50 }
51 ++__first2;
52 }
53 }
54
55 return __set_intersection_result<_InIter1, _InIter2, _OutIter>(
56 _IterOps<_AlgPolicy>::next(std::move(__first1), std::move(__last1)),
57 _IterOps<_AlgPolicy>::next(std::move(__first2), std::move(__last2)),
58 std::move(__result));
59 }
60
61 template <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
set_intersection(_InputIterator1 __first1,_InputIterator1 __last1,_InputIterator2 __first2,_InputIterator2 __last2,_OutputIterator __result,_Compare __comp)62 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator set_intersection(
63 _InputIterator1 __first1,
64 _InputIterator1 __last1,
65 _InputIterator2 __first2,
66 _InputIterator2 __last2,
67 _OutputIterator __result,
68 _Compare __comp) {
69 return std::__set_intersection<_ClassicAlgPolicy, __comp_ref_type<_Compare> >(
70 std::move(__first1),
71 std::move(__last1),
72 std::move(__first2),
73 std::move(__last2),
74 std::move(__result),
75 __comp)
76 .__out_;
77 }
78
79 template <class _InputIterator1, class _InputIterator2, class _OutputIterator>
set_intersection(_InputIterator1 __first1,_InputIterator1 __last1,_InputIterator2 __first2,_InputIterator2 __last2,_OutputIterator __result)80 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator set_intersection(
81 _InputIterator1 __first1,
82 _InputIterator1 __last1,
83 _InputIterator2 __first2,
84 _InputIterator2 __last2,
85 _OutputIterator __result) {
86 return std::__set_intersection<_ClassicAlgPolicy>(
87 std::move(__first1),
88 std::move(__last1),
89 std::move(__first2),
90 std::move(__last2),
91 std::move(__result),
92 __less<typename iterator_traits<_InputIterator1>::value_type,
93 typename iterator_traits<_InputIterator2>::value_type>())
94 .__out_;
95 }
96
97 _LIBCPP_END_NAMESPACE_STD
98
99 #endif // _LIBCPP___ALGORITHM_SET_INTERSECTION_H
100