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//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// <numeric>
// UNSUPPORTED: c++98, c++03, c++11, c++14
// template<class InputIterator>
// typename iterator_traits<InputIterator>::value_type
// reduce(InputIterator first, InputIterator last);
#include <numeric>
#include <cassert>
#include "test_iterators.h"
template <class Iter, class T>
void
test(Iter first, Iter last, T x)
{
static_assert( std::is_same_v<typename std::iterator_traits<decltype(first)>::value_type,
decltype(std::reduce(first, last))> );
assert(std::reduce(first, last) == x);
}
template <class Iter>
void
test()
{
int ia[] = {1, 2, 3, 4, 5, 6};
unsigned sa = sizeof(ia) / sizeof(ia[0]);
test(Iter(ia), Iter(ia), 0);
test(Iter(ia), Iter(ia+1), 1);
test(Iter(ia), Iter(ia+2), 3);
test(Iter(ia), Iter(ia+sa), 21);
}
template <typename T>
void test_return_type()
{
T *p = nullptr;
static_assert( std::is_same_v<T, decltype(std::reduce(p, p))> );
}
int main()
{
test_return_type<char>();
test_return_type<int>();
test_return_type<unsigned long>();
test_return_type<float>();
test_return_type<double>();
test<input_iterator<const int*> >();
test<forward_iterator<const int*> >();
test<bidirectional_iterator<const int*> >();
test<random_access_iterator<const int*> >();
test<const int*>();
}
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