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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.
//
//===----------------------------------------------------------------------===//
// <algorithm>
// template<ForwardIterator Iter, StrictWeakOrder<auto, Iter::value_type> Compare>
// requires CopyConstructible<Compare>
// Iter
// max_element(Iter first, Iter last, Compare comp);
#include <algorithm>
#include <functional>
#include <cassert>
#include "test_macros.h"
#include "test_iterators.h"
template <class Iter>
void
test(Iter first, Iter last)
{
Iter i = std::max_element(first, last, std::greater<int>());
if (first != last)
{
for (Iter j = first; j != last; ++j)
assert(!std::greater<int>()(*i, *j));
}
else
assert(i == last);
}
template <class Iter>
void
test(int N)
{
int* a = new int[N];
for (int i = 0; i < N; ++i)
a[i] = i;
std::random_shuffle(a, a+N);
test(Iter(a), Iter(a+N));
delete [] a;
}
template <class Iter>
void
test()
{
test<Iter>(0);
test<Iter>(1);
test<Iter>(2);
test<Iter>(3);
test<Iter>(10);
test<Iter>(1000);
}
template <class Iter, class Pred>
void test_eq0(Iter first, Iter last, Pred p)
{
assert(first == std::max_element(first, last, p));
}
void test_eq()
{
const int N = 10;
int* a = new int[N];
for (int i = 0; i < N; ++i)
a[i] = 10; // all the same
test_eq0(a, a+N, std::less<int>());
test_eq0(a, a+N, std::greater<int>());
delete [] a;
}
#if TEST_STD_VER >= 14
constexpr int il[] = { 2, 4, 6, 8, 7, 5, 3, 1 };
struct less { constexpr bool operator ()( const int &x, const int &y) const { return x < y; }};
#endif
void constexpr_test()
{
#if TEST_STD_VER >= 14
constexpr auto p = std::max_element(il, il+8, less());
static_assert ( *p == 8, "" );
#endif
}
int main()
{
test<forward_iterator<const int*> >();
test<bidirectional_iterator<const int*> >();
test<random_access_iterator<const int*> >();
test<const int*>();
test_eq();
constexpr_test();
}
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