//===----------------------------------------------------------------------===// // // 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. // //===----------------------------------------------------------------------===// // 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 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)); } }