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_UNION_H
10 #define _LIBCPP___ALGORITHM_SET_UNION_H
11
12 #include <__algorithm/comp.h>
13 #include <__algorithm/comp_ref_type.h>
14 #include <__algorithm/copy.h>
15 #include <__config>
16 #include <__iterator/iterator_traits.h>
17 #include <__utility/move.h>
18
19 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
20 # pragma GCC system_header
21 #endif
22
23 _LIBCPP_BEGIN_NAMESPACE_STD
24
25 template <class _InIter1, class _InIter2, class _OutIter>
26 struct __set_union_result {
27 _InIter1 __in1_;
28 _InIter2 __in2_;
29 _OutIter __out_;
30
31 // need a constructor as C++03 aggregate init is hard
32 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX17
__set_union_result__set_union_result33 __set_union_result(_InIter1&& __in_iter1, _InIter2&& __in_iter2, _OutIter&& __out_iter)
34 : __in1_(std::move(__in_iter1)), __in2_(std::move(__in_iter2)), __out_(std::move(__out_iter)) {}
35 };
36
37 template <class _Compare, class _InIter1, class _Sent1, class _InIter2, class _Sent2, class _OutIter>
__set_union(_InIter1 __first1,_Sent1 __last1,_InIter2 __first2,_Sent2 __last2,_OutIter __result,_Compare && __comp)38 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX17 __set_union_result<_InIter1, _InIter2, _OutIter> __set_union(
39 _InIter1 __first1, _Sent1 __last1, _InIter2 __first2, _Sent2 __last2, _OutIter __result, _Compare&& __comp) {
40 for (; __first1 != __last1; ++__result) {
41 if (__first2 == __last2) {
42 auto __ret1 = std::__copy_impl(std::move(__first1), std::move(__last1), std::move(__result));
43 return __set_union_result<_InIter1, _InIter2, _OutIter>(
44 std::move(__ret1.first), std::move(__first2), std::move((__ret1.second)));
45 }
46 if (__comp(*__first2, *__first1)) {
47 *__result = *__first2;
48 ++__first2;
49 } else {
50 if (!__comp(*__first1, *__first2)) {
51 ++__first2;
52 }
53 *__result = *__first1;
54 ++__first1;
55 }
56 }
57 auto __ret2 = std::__copy_impl(std::move(__first2), std::move(__last2), std::move(__result));
58 return __set_union_result<_InIter1, _InIter2, _OutIter>(
59 std::move(__first1), std::move(__ret2.first), std::move((__ret2.second)));
60 }
61
62 template <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
set_union(_InputIterator1 __first1,_InputIterator1 __last1,_InputIterator2 __first2,_InputIterator2 __last2,_OutputIterator __result,_Compare __comp)63 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator set_union(
64 _InputIterator1 __first1,
65 _InputIterator1 __last1,
66 _InputIterator2 __first2,
67 _InputIterator2 __last2,
68 _OutputIterator __result,
69 _Compare __comp) {
70 typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
71 return std::__set_union<_Comp_ref>(
72 std::move(__first1),
73 std::move(__last1),
74 std::move(__first2),
75 std::move(__last2),
76 std::move(__result),
77 __comp)
78 .__out_;
79 }
80
81 template <class _InputIterator1, class _InputIterator2, class _OutputIterator>
set_union(_InputIterator1 __first1,_InputIterator1 __last1,_InputIterator2 __first2,_InputIterator2 __last2,_OutputIterator __result)82 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator set_union(
83 _InputIterator1 __first1,
84 _InputIterator1 __last1,
85 _InputIterator2 __first2,
86 _InputIterator2 __last2,
87 _OutputIterator __result) {
88 return std::set_union(
89 std::move(__first1),
90 std::move(__last1),
91 std::move(__first2),
92 std::move(__last2),
93 std::move(__result),
94 __less<typename iterator_traits<_InputIterator1>::value_type,
95 typename iterator_traits<_InputIterator2>::value_type>());
96 }
97
98 _LIBCPP_END_NAMESPACE_STD
99
100 #endif // _LIBCPP___ALGORITHM_SET_UNION_H
101