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: c++98, c++03, c++11, c++14 11 12 // template<class InputIterator> 13 // typename iterator_traits<InputIterator>::value_type 14 // reduce(InputIterator first, InputIterator last); 15 16 #include <numeric> 17 #include <cassert> 18 19 #include "test_iterators.h" 20 21 template <class Iter, class T> 22 void 23 test(Iter first, Iter last, T x) 24 { 25 static_assert( std::is_same_v<typename std::iterator_traits<decltype(first)>::value_type, 26 decltype(std::reduce(first, last))> ); 27 assert(std::reduce(first, last) == x); 28 } 29 30 template <class Iter> 31 void 32 test() 33 { 34 int ia[] = {1, 2, 3, 4, 5, 6}; 35 unsigned sa = sizeof(ia) / sizeof(ia[0]); 36 test(Iter(ia), Iter(ia), 0); 37 test(Iter(ia), Iter(ia+1), 1); 38 test(Iter(ia), Iter(ia+2), 3); 39 test(Iter(ia), Iter(ia+sa), 21); 40 } 41 42 template <typename T> 43 void test_return_type() 44 { 45 T *p = nullptr; 46 static_assert( std::is_same_v<T, decltype(std::reduce(p, p))> ); 47 } 48 49 int main() 50 { 51 test_return_type<char>(); 52 test_return_type<int>(); 53 test_return_type<unsigned long>(); 54 test_return_type<float>(); 55 test_return_type<double>(); 56 57 test<input_iterator<const int*> >(); 58 test<forward_iterator<const int*> >(); 59 test<bidirectional_iterator<const int*> >(); 60 test<random_access_iterator<const int*> >(); 61 test<const int*>(); 62 } 63