prime.cpp

#include <iostream>

bool test_prime(const uint64_t n)
{
    if (n == 2 || n == 3)
        return true;

    if (n <= 1 || n % 2 == 0 || n % 3 == 0)
        return false;

    for (uint64_t i = 5; i * i <= n; i += 6)
    {
        if (n % i == 0 || n % (i + 2) == 0)
            return false;
    }

    return true;
}

int main(int argc, char const* argv[])
{
    std::cout << std::boolalpha << test_prime(11) << '\n'; 
    std::cout << std::boolalpha << test_prime(321564613654653) << '\n'; 
    std::cout << std::boolalpha << test_prime(27644437) << '\n'; 
    std::cout << std::boolalpha << test_prime(276444378) << '\n'; 
}