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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// <algorithm>
// template<InputIterator Iter, Predicate<auto, Iter::value_type> Pred>
// requires CopyConstructible<Pred>
// constexpr Iter::difference_type // constexpr after C++17
// count_if(Iter first, Iter last, Pred pred);
#include <algorithm>
#include <functional>
#include <cassert>
#include "test_macros.h"
#include "test_iterators.h"
struct eq {
TEST_CONSTEXPR eq (int val) : v(val) {}
TEST_CONSTEXPR bool operator () (int v2) const { return v == v2; }
int v;
};
#if TEST_STD_VER > 17
TEST_CONSTEXPR bool test_constexpr() {
int ia[] = {0, 1, 2, 2, 0, 1, 2, 3};
int ib[] = {1, 2, 3, 4, 5, 6};
return (std::count_if(std::begin(ia), std::end(ia), eq(2)) == 3)
&& (std::count_if(std::begin(ib), std::end(ib), eq(9)) == 0)
;
}
#endif
int main(int, char**)
{
int ia[] = {0, 1, 2, 2, 0, 1, 2, 3};
const unsigned sa = sizeof(ia)/sizeof(ia[0]);
assert(std::count_if(input_iterator<const int*>(ia),
input_iterator<const int*>(ia + sa),
eq(2)) == 3);
assert(std::count_if(input_iterator<const int*>(ia),
input_iterator<const int*>(ia + sa),
eq(7)) == 0);
assert(std::count_if(input_iterator<const int*>(ia),
input_iterator<const int*>(ia),
eq(2)) == 0);
#if TEST_STD_VER > 17
static_assert(test_constexpr());
#endif
return 0;
}
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