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 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 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 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
