xref: /llvm-project/libcxx/include/__algorithm/set_intersection.h (revision 5aaefa510ef055e8f044ca89e352d4313f3aba49)
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 <__config>
15 #include <__iterator/iterator_traits.h>
16 
17 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
18 #  pragma GCC system_header
19 #  pragma clang include_instead(<algorithm>)
20 #endif
21 
22 _LIBCPP_BEGIN_NAMESPACE_STD
23 
24 template <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
25 _LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
26 __set_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
27                    _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
28 {
29     while (__first1 != __last1 && __first2 != __last2)
30     {
31         if (__comp(*__first1, *__first2))
32             ++__first1;
33         else
34         {
35             if (!__comp(*__first2, *__first1))
36             {
37                 *__result = *__first1;
38                 ++__result;
39                 ++__first1;
40             }
41             ++__first2;
42         }
43     }
44     return __result;
45 }
46 
47 template <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
48 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
49 _OutputIterator
50 set_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
51                  _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
52 {
53     typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
54     return _VSTD::__set_intersection<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
55 }
56 
57 template <class _InputIterator1, class _InputIterator2, class _OutputIterator>
58 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
59 _OutputIterator
60 set_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
61                  _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
62 {
63     return _VSTD::set_intersection(__first1, __last1, __first2, __last2, __result,
64                                   __less<typename iterator_traits<_InputIterator1>::value_type,
65                                          typename iterator_traits<_InputIterator2>::value_type>());
66 }
67 
68 _LIBCPP_END_NAMESPACE_STD
69 
70 #endif // _LIBCPP___ALGORITHM_SET_INTERSECTION_H
71