1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
|
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++03, c++11, c++14
// UNSUPPORTED: clang-8
// UNSUPPORTED: gcc-9
// <numeric>
// Became constexpr in C++20
// template<class InputIterator, class OutputIterator, class T, class BinaryOperation>
// OutputIterator
// inclusive_scan(InputIterator first, InputIterator last,
// OutputIterator result,
// BinaryOperation binary_op, T init); // C++17
#include <numeric>
#include <algorithm>
#include <array>
#include <cassert>
#include <functional>
#include <iterator>
#include "test_macros.h"
#include "test_iterators.h"
template <class Iter1, class T, class Op>
TEST_CONSTEXPR_CXX20 void
test(Iter1 first, Iter1 last, Op op, T init, const T *rFirst, const T *rLast)
{
assert((rLast - rFirst) <= 5); // or else increase the size of "out"
T out[5];
// Not in place
T *end = std::inclusive_scan(first, last, out, op, init);
assert(std::equal(out, end, rFirst, rLast));
// In place
std::copy(first, last, out);
end = std::inclusive_scan(out, end, out, op, init);
assert(std::equal(out, end, rFirst, rLast));
}
template <class Iter>
TEST_CONSTEXPR_CXX20 void
test()
{
int ia[] = {1, 3, 5, 7, 9};
const int pRes[] = {1, 4, 9, 16, 25};
const int mRes[] = {1, 3, 15, 105, 945};
const unsigned sa = sizeof(ia) / sizeof(ia[0]);
static_assert(sa == sizeof(pRes) / sizeof(pRes[0])); // just to be sure
static_assert(sa == sizeof(mRes) / sizeof(mRes[0])); // just to be sure
for (unsigned int i = 0; i < sa; ++i ) {
test(Iter(ia), Iter(ia + i), std::plus<>(), 0, pRes, pRes + i);
test(Iter(ia), Iter(ia + i), std::multiplies<>(), 1, mRes, mRes + i);
}
}
constexpr size_t triangle(size_t n) { return n*(n+1)/2; }
// Basic sanity
TEST_CONSTEXPR_CXX20 void
basic_tests()
{
{
std::array<size_t, 10> v;
std::fill(v.begin(), v.end(), 3);
std::inclusive_scan(v.begin(), v.end(), v.begin(), std::plus<>(), size_t{50});
for (size_t i = 0; i < v.size(); ++i)
assert(v[i] == 50 + (i+1) * 3);
}
{
std::array<size_t, 10> v;
std::iota(v.begin(), v.end(), 0);
std::inclusive_scan(v.begin(), v.end(), v.begin(), std::plus<>(), size_t{40});
for (size_t i = 0; i < v.size(); ++i)
assert(v[i] == 40 + triangle(i));
}
{
std::array<size_t, 10> v;
std::iota(v.begin(), v.end(), 1);
std::inclusive_scan(v.begin(), v.end(), v.begin(), std::plus<>(), size_t{30});
for (size_t i = 0; i < v.size(); ++i)
assert(v[i] == 30 + triangle(i + 1));
}
{
std::array<size_t, 0> v, res;
std::inclusive_scan(v.begin(), v.end(), res.begin(), std::plus<>(), size_t{40});
assert(res.empty());
}
// Make sure that the calculations are done using the init typedef
{
std::array<unsigned char, 10> v;
std::iota(v.begin(), v.end(), static_cast<unsigned char>(1));
std::array<size_t, 10> res;
std::inclusive_scan(v.begin(), v.end(), res.begin(), std::multiplies<>(), size_t{1});
assert(res.size() == 10);
size_t j = 1;
assert(res[0] == 1);
for (size_t i = 1; i < v.size(); ++i)
{
j *= i + 1;
assert(res[i] == j);
}
}
}
TEST_CONSTEXPR_CXX20 bool
test()
{
basic_tests();
// All the iterator categories
test<cpp17_input_iterator <const int*> >();
test<forward_iterator <const int*> >();
test<bidirectional_iterator<const int*> >();
test<random_access_iterator<const int*> >();
test<const int*>();
test< int*>();
return true;
}
int main(int, char**)
{
test();
#if TEST_STD_VER > 17
static_assert(test());
#endif
return 0;
}
|
