1 //===----------------------------------------------------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is dual licensed under the MIT and the University of Illinois Open
6 // Source Licenses. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 // <algorithm>
11
12 // template<class ForwardIterator, class Size, class T, class BinaryPredicate>
13 // constexpr ForwardIterator // constexpr after C++17
14 // search_n(ForwardIterator first, ForwardIterator last, Size count,
15 // const T& value, BinaryPredicate pred);
16
17 #include <algorithm>
18 #include <cassert>
19
20 #include "test_macros.h"
21 #include "test_iterators.h"
22 #include "user_defined_integral.hpp"
23
24 #if TEST_STD_VER > 17
eq(int a,int b)25 TEST_CONSTEXPR bool eq(int a, int b) { return a == b; }
26
test_constexpr()27 TEST_CONSTEXPR bool test_constexpr() {
28 int ia[] = {0, 0, 1, 1, 2, 2};
29 return (std::search_n(std::begin(ia), std::end(ia), 1, 0, eq) == ia)
30 && (std::search_n(std::begin(ia), std::end(ia), 2, 1, eq) == ia+2)
31 && (std::search_n(std::begin(ia), std::end(ia), 1, 3, eq) == std::end(ia))
32 ;
33 }
34 #endif
35
36 struct count_equal
37 {
38 static unsigned count;
39 template <class T>
operator ()count_equal40 bool operator()(const T& x, const T& y)
41 {++count; return x == y;}
42 };
43
44 unsigned count_equal::count = 0;
45
46
47 template <class Iter>
48 void
test()49 test()
50 {
51 int ia[] = {0, 1, 2, 3, 4, 5};
52 const unsigned sa = sizeof(ia)/sizeof(ia[0]);
53 count_equal::count = 0;
54 assert(std::search_n(Iter(ia), Iter(ia+sa), 0, 0, count_equal()) == Iter(ia));
55 assert(count_equal::count <= sa);
56 count_equal::count = 0;
57 assert(std::search_n(Iter(ia), Iter(ia+sa), 1, 0, count_equal()) == Iter(ia+0));
58 assert(count_equal::count <= sa);
59 count_equal::count = 0;
60 assert(std::search_n(Iter(ia), Iter(ia+sa), 2, 0, count_equal()) == Iter(ia+sa));
61 assert(count_equal::count <= sa);
62 count_equal::count = 0;
63 assert(std::search_n(Iter(ia), Iter(ia+sa), sa, 0, count_equal()) == Iter(ia+sa));
64 assert(count_equal::count <= sa);
65 count_equal::count = 0;
66 assert(std::search_n(Iter(ia), Iter(ia+sa), 0, 3, count_equal()) == Iter(ia));
67 assert(count_equal::count <= sa);
68 count_equal::count = 0;
69 assert(std::search_n(Iter(ia), Iter(ia+sa), 1, 3, count_equal()) == Iter(ia+3));
70 assert(count_equal::count <= sa);
71 count_equal::count = 0;
72 assert(std::search_n(Iter(ia), Iter(ia+sa), 2, 3, count_equal()) == Iter(ia+sa));
73 assert(count_equal::count <= sa);
74 count_equal::count = 0;
75 assert(std::search_n(Iter(ia), Iter(ia+sa), sa, 3, count_equal()) == Iter(ia+sa));
76 assert(count_equal::count <= sa);
77 count_equal::count = 0;
78 assert(std::search_n(Iter(ia), Iter(ia+sa), 0, 5, count_equal()) == Iter(ia));
79 assert(count_equal::count <= sa);
80 count_equal::count = 0;
81 assert(std::search_n(Iter(ia), Iter(ia+sa), 1, 5, count_equal()) == Iter(ia+5));
82 assert(count_equal::count <= sa);
83 count_equal::count = 0;
84 assert(std::search_n(Iter(ia), Iter(ia+sa), 2, 5, count_equal()) == Iter(ia+sa));
85 assert(count_equal::count <= sa);
86 count_equal::count = 0;
87 assert(std::search_n(Iter(ia), Iter(ia+sa), sa, 5, count_equal()) == Iter(ia+sa));
88 assert(count_equal::count <= sa);
89 count_equal::count = 0;
90
91 int ib[] = {0, 0, 1, 1, 2, 2};
92 const unsigned sb = sizeof(ib)/sizeof(ib[0]);
93 assert(std::search_n(Iter(ib), Iter(ib+sb), 0, 0, count_equal()) == Iter(ib));
94 assert(count_equal::count <= sb);
95 count_equal::count = 0;
96 assert(std::search_n(Iter(ib), Iter(ib+sb), 1, 0, count_equal()) == Iter(ib+0));
97 assert(count_equal::count <= sb);
98 count_equal::count = 0;
99 assert(std::search_n(Iter(ib), Iter(ib+sb), 2, 0, count_equal()) == Iter(ib+0));
100 assert(count_equal::count <= sb);
101 count_equal::count = 0;
102 assert(std::search_n(Iter(ib), Iter(ib+sb), 3, 0, count_equal()) == Iter(ib+sb));
103 assert(count_equal::count <= sb);
104 count_equal::count = 0;
105 assert(std::search_n(Iter(ib), Iter(ib+sb), sb, 0, count_equal()) == Iter(ib+sb));
106 assert(count_equal::count <= sb);
107 count_equal::count = 0;
108 assert(std::search_n(Iter(ib), Iter(ib+sb), 0, 1, count_equal()) == Iter(ib));
109 assert(count_equal::count <= sb);
110 count_equal::count = 0;
111 assert(std::search_n(Iter(ib), Iter(ib+sb), 1, 1, count_equal()) == Iter(ib+2));
112 assert(count_equal::count <= sb);
113 count_equal::count = 0;
114 assert(std::search_n(Iter(ib), Iter(ib+sb), 2, 1, count_equal()) == Iter(ib+2));
115 assert(count_equal::count <= sb);
116 count_equal::count = 0;
117 assert(std::search_n(Iter(ib), Iter(ib+sb), 3, 1, count_equal()) == Iter(ib+sb));
118 assert(count_equal::count <= sb);
119 count_equal::count = 0;
120 assert(std::search_n(Iter(ib), Iter(ib+sb), sb, 1, count_equal()) == Iter(ib+sb));
121 assert(count_equal::count <= sb);
122 count_equal::count = 0;
123 assert(std::search_n(Iter(ib), Iter(ib+sb), 0, 2, count_equal()) == Iter(ib));
124 assert(count_equal::count <= sb);
125 count_equal::count = 0;
126 assert(std::search_n(Iter(ib), Iter(ib+sb), 1, 2, count_equal()) == Iter(ib+4));
127 assert(count_equal::count <= sb);
128 count_equal::count = 0;
129 assert(std::search_n(Iter(ib), Iter(ib+sb), 2, 2, count_equal()) == Iter(ib+4));
130 assert(count_equal::count <= sb);
131 count_equal::count = 0;
132 assert(std::search_n(Iter(ib), Iter(ib+sb), 3, 2, count_equal()) == Iter(ib+sb));
133 assert(count_equal::count <= sb);
134 count_equal::count = 0;
135 assert(std::search_n(Iter(ib), Iter(ib+sb), sb, 2, count_equal()) == Iter(ib+sb));
136 assert(count_equal::count <= sb);
137 count_equal::count = 0;
138
139 int ic[] = {0, 0, 0};
140 const unsigned sc = sizeof(ic)/sizeof(ic[0]);
141 assert(std::search_n(Iter(ic), Iter(ic+sc), 0, 0, count_equal()) == Iter(ic));
142 assert(count_equal::count <= sc);
143 count_equal::count = 0;
144 assert(std::search_n(Iter(ic), Iter(ic+sc), 1, 0, count_equal()) == Iter(ic));
145 assert(count_equal::count <= sc);
146 count_equal::count = 0;
147 assert(std::search_n(Iter(ic), Iter(ic+sc), 2, 0, count_equal()) == Iter(ic));
148 assert(count_equal::count <= sc);
149 count_equal::count = 0;
150 assert(std::search_n(Iter(ic), Iter(ic+sc), 3, 0, count_equal()) == Iter(ic));
151 assert(count_equal::count <= sc);
152 count_equal::count = 0;
153 assert(std::search_n(Iter(ic), Iter(ic+sc), 4, 0, count_equal()) == Iter(ic+sc));
154 assert(count_equal::count <= sc);
155 count_equal::count = 0;
156
157 // Check that we properly convert the size argument to an integral.
158 TEST_IGNORE_NODISCARD std::search_n(Iter(ic), Iter(ic+sc), UserDefinedIntegral<unsigned>(4), 0, count_equal());
159 count_equal::count = 0;
160 }
161
main()162 int main()
163 {
164 test<forward_iterator<const int*> >();
165 test<bidirectional_iterator<const int*> >();
166 test<random_access_iterator<const int*> >();
167
168 #if TEST_STD_VER > 17
169 static_assert(test_constexpr());
170 #endif
171 }
172