primes.c

/*
 *To-do:
 *  - Use bitwise operations for everything
 *  - Add ability to output to a file
 */

#include <stdio.h>
#include <stdbool.h>
#include <limits.h>

bool isPrime(unsigned long long num);

bool isPrime(unsigned long long num) {
    unsigned long long c = (num >> 1);
    for( c; c >= 2; c-- ) {
        if ( num % c == 0 ) return false;
    }
    return true;
}

int main(void) {
    unsigned long long c;
    for ( c = 2; c <= ULLONG_MAX; c++ ) {
        if ( isPrime(c) == true ) printf("%d\n", c);
    }
    return 0;
}