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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.
//
//===----------------------------------------------------------------------===//
//
// REQUIRES: long_tests
// Not a portable test
// <__hash_table>
// size_t __next_prime(size_t n);
// If n == 0, return 0, else return the lowest prime greater than or equal to n
#include <__hash_table>
#include <cassert>
bool
is_prime(size_t n)
{
switch (n)
{
case 0:
case 1:
return false;
}
for (size_t i = 2; i*i <= n; ++i)
{
if (n % i == 0)
return false;
}
return true;
}
int main()
{
assert(std::__next_prime(0) == 0);
for (std::size_t n = 1; n <= 100000; ++n)
{
std::size_t p = std::__next_prime(n);
assert(p >= n);
for (std::size_t i = n; i < p; ++i)
assert(!is_prime(i));
assert(is_prime(p));
}
}
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