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 // <numeric>
11 // UNSUPPORTED: c++98, c++03, c++11, c++14
12
13 // template<class InputIterator, class OutputIterator, class T, class BinaryOperation>
14 // OutputIterator
15 // exclusive_scan(InputIterator first, InputIterator last,
16 // OutputIterator result,
17 // T init, BinaryOperation binary_op); // C++17
18
19 #include <numeric>
20 #include <algorithm>
21 #include <cassert>
22 #include <functional>
23 #include <iterator>
24 #include <vector>
25
26 #include "test_iterators.h"
27
28 template <class Iter1, class T, class Op, class Iter2>
29 void
test(Iter1 first,Iter1 last,T init,Op op,Iter2 rFirst,Iter2 rLast)30 test(Iter1 first, Iter1 last, T init, Op op, Iter2 rFirst, Iter2 rLast)
31 {
32 std::vector<typename std::iterator_traits<Iter1>::value_type> v;
33
34 // Not in place
35 std::exclusive_scan(first, last, std::back_inserter(v), init, op);
36 assert(std::equal(v.begin(), v.end(), rFirst, rLast));
37
38 // In place
39 v.clear();
40 v.assign(first, last);
41 std::exclusive_scan(v.begin(), v.end(), v.begin(), init, op);
42 assert(std::equal(v.begin(), v.end(), rFirst, rLast));
43 }
44
45
46 template <class Iter>
47 void
test()48 test()
49 {
50 int ia[] = {1, 3, 5, 7, 9};
51 const int pRes[] = {0, 1, 4, 9, 16};
52 const int mRes[] = {1, 1, 3, 15, 105};
53 const unsigned sa = sizeof(ia) / sizeof(ia[0]);
54 static_assert(sa == sizeof(pRes) / sizeof(pRes[0])); // just to be sure
55 static_assert(sa == sizeof(mRes) / sizeof(mRes[0])); // just to be sure
56
57 for (unsigned int i = 0; i < sa; ++i ) {
58 test(Iter(ia), Iter(ia + i), 0, std::plus<>(), pRes, pRes + i);
59 test(Iter(ia), Iter(ia + i), 1, std::multiplies<>(), mRes, mRes + i);
60 }
61 }
62
main()63 int main()
64 {
65 // All the iterator categories
66 test<input_iterator <const int*> >();
67 test<forward_iterator <const int*> >();
68 test<bidirectional_iterator<const int*> >();
69 test<random_access_iterator<const int*> >();
70 test<const int*>();
71 test< int*>();
72
73 // Make sure that the calculations are done using the init typedef
74 {
75 std::vector<unsigned char> v(10);
76 std::iota(v.begin(), v.end(), static_cast<unsigned char>(1));
77 std::vector<int> res;
78 std::exclusive_scan(v.begin(), v.end(), std::back_inserter(res), 1, std::multiplies<>());
79
80 assert(res.size() == 10);
81 int j = 1;
82 assert(res[0] == 1);
83 for (size_t i = 1; i < v.size(); ++i)
84 {
85 j *= i;
86 assert(res[i] == j);
87 }
88 }
89 }
90