Loops.java

public class Loops{
    
    public int fact(int n){
        if (n == 1)
            return n;
        else
            return n * fact(n - 1);
    }

    public int fact2(int n){
        int counter = 1;
        int ans = 1;
        while (counter <= n){
            ans = ans * counter;
            counter++;
        }
        return ans;
    }

    public int gcd(int a, int b){
	int counter;
	if (a >= b){
	    counter = a;
	}else{
	    counter = b;
	}
	boolean div = false;
	while (div == false){
	    if (a % counter == 0 && b % counter == 0){
		div = true;
	    }else{
	    	counter --;
	    }
	}
	return counter;
	
   }

   public int gcdFor(int a, int b){
        int counter;
        int gcd = 1;
        int smaller;
        if (a <= b){
            smaller = a;
        }else{
            smaller = b;
        }
        for (counter = 2;counter <= smaller; counter ++){
            if (a % counter == 0 && b % counter == 0){
                gcd = counter;
            }
        }
        return gcd;
   }

   public int gcd2(int a, int b){
	int aparam = a;
	int bparam = b;
	boolean is0 = false;
	while (is0 == false){
	    if (bparam == 0){
		is0 = true;
	    }else{
		int temp = aparam % bparam;
	        aparam = bparam;
		bparam = temp;
	    }
	}
	return aparam;
}

   public boolean isPrime(int n){
        double upperBound = n/2;
        int counter = 2;
        while (counter <= upperBound){
            if (n % counter == 0){
                return false;
            }
            counter ++;
        }
        return true;
   }
}