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 // <numeric>
10 // UNSUPPORTED: clang-8
11 // UNSUPPORTED: gcc-9
12 
13 // Became constexpr in C++20
14 // template <InputIterator Iter1, InputIterator Iter2, MoveConstructible T>
15 //   requires HasMultiply<Iter1::reference, Iter2::reference>
16 //         && HasPlus<T, HasMultiply<Iter1::reference, Iter2::reference>::result_type>
17 //         && HasAssign<T,
18 //                      HasPlus<T,
19 //                              HasMultiply<Iter1::reference,
20 //                                          Iter2::reference>::result_type>::result_type>
21 //   T
22 //   inner_product(Iter1 first1, Iter1 last1, Iter2 first2, T init);
23 
24 #include <numeric>
25 #include <cassert>
26 
27 #include "test_macros.h"
28 #include "test_iterators.h"
29 
30 template <class Iter1, class Iter2, class T>
31 TEST_CONSTEXPR_CXX20 void
32 test(Iter1 first1, Iter1 last1, Iter2 first2, T init, T x)
33 {
34     assert(std::inner_product(first1, last1, first2, init) == x);
35 }
36 
37 template <class Iter1, class Iter2>
38 TEST_CONSTEXPR_CXX20 void
39 test()
40 {
41     int a[] = {1, 2, 3, 4, 5, 6};
42     int b[] = {6, 5, 4, 3, 2, 1};
43     unsigned sa = sizeof(a) / sizeof(a[0]);
44     test(Iter1(a), Iter1(a), Iter2(b), 0, 0);
45     test(Iter1(a), Iter1(a), Iter2(b), 10, 10);
46     test(Iter1(a), Iter1(a+1), Iter2(b), 0, 6);
47     test(Iter1(a), Iter1(a+1), Iter2(b), 10, 16);
48     test(Iter1(a), Iter1(a+2), Iter2(b), 0, 16);
49     test(Iter1(a), Iter1(a+2), Iter2(b), 10, 26);
50     test(Iter1(a), Iter1(a+sa), Iter2(b), 0, 56);
51     test(Iter1(a), Iter1(a+sa), Iter2(b), 10, 66);
52 }
53 
54 TEST_CONSTEXPR_CXX20 bool
55 test()
56 {
57     test<cpp17_input_iterator<const int*>, cpp17_input_iterator<const int*> >();
58     test<cpp17_input_iterator<const int*>, forward_iterator<const int*> >();
59     test<cpp17_input_iterator<const int*>, bidirectional_iterator<const int*> >();
60     test<cpp17_input_iterator<const int*>, random_access_iterator<const int*> >();
61     test<cpp17_input_iterator<const int*>, const int*>();
62 
63     test<forward_iterator<const int*>, cpp17_input_iterator<const int*> >();
64     test<forward_iterator<const int*>, forward_iterator<const int*> >();
65     test<forward_iterator<const int*>, bidirectional_iterator<const int*> >();
66     test<forward_iterator<const int*>, random_access_iterator<const int*> >();
67     test<forward_iterator<const int*>, const int*>();
68 
69     test<bidirectional_iterator<const int*>, cpp17_input_iterator<const int*> >();
70     test<bidirectional_iterator<const int*>, forward_iterator<const int*> >();
71     test<bidirectional_iterator<const int*>, bidirectional_iterator<const int*> >();
72     test<bidirectional_iterator<const int*>, random_access_iterator<const int*> >();
73     test<bidirectional_iterator<const int*>, const int*>();
74 
75     test<random_access_iterator<const int*>, cpp17_input_iterator<const int*> >();
76     test<random_access_iterator<const int*>, forward_iterator<const int*> >();
77     test<random_access_iterator<const int*>, bidirectional_iterator<const int*> >();
78     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
79     test<random_access_iterator<const int*>, const int*>();
80 
81     test<const int*, cpp17_input_iterator<const int*> >();
82     test<const int*, forward_iterator<const int*> >();
83     test<const int*, bidirectional_iterator<const int*> >();
84     test<const int*, random_access_iterator<const int*> >();
85     test<const int*, const int*>();
86 
87     return true;
88 }
89 
90 int main(int, char**)
91 {
92     test();
93 #if TEST_STD_VER > 17
94     static_assert(test());
95 #endif
96     return 0;
97 }
98