Wokstym

 /* Optimized for not checking multiples of 3 */
    private static boolean isPrime(double val) {
        if (val == 0 || val == 1) return false;
        if (val == 2 || val == 3) return true;
        if (val % 2 == 0 || val % 3 == 0) return false;

        for (int i = 5; i <= Math.sqrt(val); i += 4) {
            if (val % i == 0) return false;
            i += 2;
            if (val % i == 0) return false;

Wokstym

# initialization file (not found)