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<ForwardIterator Iter>
12 //   requires EqualityComparable<Iter::value_type>
13 //   constexpr Iter  // constexpr after C++17
14 //   adjacent_find(Iter first, Iter last);
15 
16 #include <algorithm>
17 #include <cassert>
18 
19 #include "test_macros.h"
20 #include "test_iterators.h"
21 
22 #if TEST_STD_VER > 17
23 TEST_CONSTEXPR bool test_constexpr() {
24     int ia[] = {0, 1, 2, 2, 0, 1, 2, 3};
25     int ib[] = {0, 1, 2, 7, 0, 1, 2, 3};
26 
27     return  (std::adjacent_find(std::begin(ia), std::end(ia)) == ia+2)
28          && (std::adjacent_find(std::begin(ib), std::end(ib)) == std::end(ib))
29          ;
30     }
31 #endif
32 
33 int main(int, char**)
34 {
35     int ia[] = {0, 1, 2, 2, 0, 1, 2, 3};
36     const unsigned sa = sizeof(ia)/sizeof(ia[0]);
37     assert(std::adjacent_find(forward_iterator<const int*>(ia),
38                               forward_iterator<const int*>(ia + sa)) ==
39                               forward_iterator<const int*>(ia+2));
40     assert(std::adjacent_find(forward_iterator<const int*>(ia),
41                               forward_iterator<const int*>(ia)) ==
42                               forward_iterator<const int*>(ia));
43     assert(std::adjacent_find(forward_iterator<const int*>(ia+3),
44                               forward_iterator<const int*>(ia + sa)) ==
45                               forward_iterator<const int*>(ia+sa));
46 
47 #if TEST_STD_VER > 17
48     static_assert(test_constexpr());
49 #endif
50 
51   return 0;
52 }
53