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// <algorithm>
10
11// template<InputIterator InIter1, InputIterator InIter2, typename OutIter>
12// requires OutputIterator<OutIter, InIter1::reference>
13// && OutputIterator<OutIter, InIter2::reference>
14// && HasLess<InIter2::value_type, InIter1::value_type>
15// && HasLess<InIter1::value_type, InIter2::value_type>
16// constexpr OutIter // constexpr after C++17
17// set_difference(InIter1 first1, InIter1 last1, InIter2 first2, InIter2 last2,
18// OutIter result);
19
20#include <algorithm>
21#include <cassert>
22
23#include "test_macros.h"
24#include "test_iterators.h"
25#include "../../sortable_helpers.h"
26
27template<class T, class Iter1, class Iter2, class OutIter>
28TEST_CONSTEXPR_CXX20 void test4()
29{
30 const T a[] = {11, 33, 31, 41};
31 const T b[] = {22, 32, 43, 42, 52};
32 {
33 T result[20] = {};
34 T expected[] = {11, 31};
35 OutIter end = std::set_difference(Iter1(a), Iter1(a+4), Iter2(b), Iter2(b+5), OutIter(result));
36 assert(std::lexicographical_compare(result, base(end), expected, expected+2, T::less) == 0);
37 for (const T *it = base(end); it != result+20; ++it) {
38 assert(it->value == 0);
39 }
40 }
41 {
42 T result[20] = {};
43 T expected[] = {22, 42, 52};
44 OutIter end = std::set_difference(Iter1(b), Iter1(b+5), Iter2(a), Iter2(a+4), OutIter(result));
45 assert(std::lexicographical_compare(result, base(end), expected, expected+3, T::less) == 0);
46 for (const T *it = base(end); it != result+20; ++it) {
47 assert(it->value == 0);
48 }
49 }
50}
51
52template<class T, class Iter1, class Iter2>
53TEST_CONSTEXPR_CXX20 void test3()
54{
55 test4<T, Iter1, Iter2, cpp17_output_iterator<T*> >();
56 test4<T, Iter1, Iter2, forward_iterator<T*> >();
57 test4<T, Iter1, Iter2, bidirectional_iterator<T*> >();
58 test4<T, Iter1, Iter2, random_access_iterator<T*> >();
59 test4<T, Iter1, Iter2, T*>();
60}
61
62template<class T, class Iter1>
63TEST_CONSTEXPR_CXX20 void test2()
64{
65 test3<T, Iter1, cpp17_input_iterator<const T*> >();
66 test3<T, Iter1, forward_iterator<const T*> >();
67 test3<T, Iter1, bidirectional_iterator<const T*> >();
68 test3<T, Iter1, random_access_iterator<const T*> >();
69 test3<T, Iter1, const T*>();
70}
71
72template<class T>
73TEST_CONSTEXPR_CXX20 void test1()
74{
75 test2<T, cpp17_input_iterator<const T*> >();
76 test2<T, forward_iterator<const T*> >();
77 test2<T, bidirectional_iterator<const T*> >();
78 test2<T, random_access_iterator<const T*> >();
79 test2<T, const T*>();
80}
81
82TEST_CONSTEXPR_CXX20 bool test()
83{
84 test1<TrivialSortable>();
85 test1<NonTrivialSortable>();
86 return true;
87}
88
89int main(int, char**)
90{
91 test();
92#if TEST_STD_VER > 17
93 static_assert(test());
94#endif
95
96 return 0;
97}
98

source code of libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.difference/set_difference.pass.cpp