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<class ForwardIterator, class Predicate>
12 //     constexpr ForwardIterator       // constexpr after C++17
13 //     partition_point(ForwardIterator first, ForwardIterator last, Predicate pred);
14 
15 #include <algorithm>
16 #include <cassert>
17 
18 #include "test_macros.h"
19 #include "test_iterators.h"
20 
21 struct is_odd
22 {
23     TEST_CONSTEXPR bool operator()(const int& i) const {return i & 1;}
24 };
25 
26 
27 #if TEST_STD_VER > 17
28 TEST_CONSTEXPR bool test_constexpr() {
29     int ia[] = {1, 3, 5, 2, 4, 6};
30     int ib[] = {1, 2, 3, 4, 5, 6};
31     return    (std::partition_point(std::begin(ia), std::end(ia), is_odd()) == ia+3)
32            && (std::partition_point(std::begin(ib), std::end(ib), is_odd()) == ib+1)
33            ;
34     }
35 #endif
36 
37 
38 int main(int, char**)
39 {
40     {
41         const int ia[] = {2, 4, 6, 8, 10};
42         assert(std::partition_point(forward_iterator<const int*>(std::begin(ia)),
43                                     forward_iterator<const int*>(std::end(ia)),
44                                     is_odd()) == forward_iterator<const int*>(ia));
45     }
46     {
47         const int ia[] = {1, 2, 4, 6, 8};
48         assert(std::partition_point(forward_iterator<const int*>(std::begin(ia)),
49                                     forward_iterator<const int*>(std::end(ia)),
50                                     is_odd()) == forward_iterator<const int*>(ia + 1));
51     }
52     {
53         const int ia[] = {1, 3, 2, 4, 6};
54         assert(std::partition_point(forward_iterator<const int*>(std::begin(ia)),
55                                     forward_iterator<const int*>(std::end(ia)),
56                                     is_odd()) == forward_iterator<const int*>(ia + 2));
57     }
58     {
59         const int ia[] = {1, 3, 5, 2, 4, 6};
60         assert(std::partition_point(forward_iterator<const int*>(std::begin(ia)),
61                                     forward_iterator<const int*>(std::end(ia)),
62                                     is_odd()) == forward_iterator<const int*>(ia + 3));
63     }
64     {
65         const int ia[] = {1, 3, 5, 7, 2, 4};
66         assert(std::partition_point(forward_iterator<const int*>(std::begin(ia)),
67                                     forward_iterator<const int*>(std::end(ia)),
68                                     is_odd()) == forward_iterator<const int*>(ia + 4));
69     }
70     {
71         const int ia[] = {1, 3, 5, 7, 9, 2};
72         assert(std::partition_point(forward_iterator<const int*>(std::begin(ia)),
73                                     forward_iterator<const int*>(std::end(ia)),
74                                     is_odd()) == forward_iterator<const int*>(ia + 5));
75     }
76     {
77         const int ia[] = {1, 3, 5, 7, 9, 11};
78         assert(std::partition_point(forward_iterator<const int*>(std::begin(ia)),
79                                     forward_iterator<const int*>(std::end(ia)),
80                                     is_odd()) == forward_iterator<const int*>(ia + 6));
81     }
82     {
83         const int ia[] = {1, 3, 5, 2, 4, 6, 7};
84         assert(std::partition_point(forward_iterator<const int*>(std::begin(ia)),
85                                     forward_iterator<const int*>(std::begin(ia)),
86                                     is_odd()) == forward_iterator<const int*>(ia));
87     }
88 
89 #if TEST_STD_VER > 17
90     static_assert(test_constexpr());
91 #endif
92 
93   return 0;
94 }
95