You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
55 lines
1.1 KiB
C++
55 lines
1.1 KiB
C++
//===----------------------------------------------------------------------===//
|
|
//
|
|
// 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
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// 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>
|
|
|
|
#include "test_macros.h"
|
|
|
|
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(int, char**)
|
|
{
|
|
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));
|
|
}
|
|
|
|
return 0;
|
|
}
|