Prime Number Finder calculation error

Question

I am trying to make a prime number finder in Java, and I am aware that there are plenty already out there. I am getting a calculation error when I run it, and no 'quick fixes.' Here is the error: "Exception in thread "main" java.lang.ArithmeticException: / by zero at PrimeNumber.main(PrimeNumber.java:12)"

Here is the code:

public class PrimeNumber {
    public static void main(String rane[]){

        int f1 = 0;
        int f2 = 0;
        int m = 0;
        int p = 0;

        loop:
        for (p = f1 % f2; p > 0; f1 += 1){
            if (f1 < 50){
                //Do nothing
            }else{
                f2 += 1;
                if (f2 > 50){
                    System.out.println("Done!");
                    break;
                }
            }
            if (p == m){
                f1 += 1;
                f2 += 2;
                m = 0;
                break loop;
            }   
        }
    }
}

Please let me know if I can shorten this code or make it better. Thanks!

Answer 1

Well the first iteration of the for loop calculates

p = f1 % f2

but f2 is 0. And for calculating the modulo a division is made. Why not start out with meaningful values?