public class FactorialIter {

    public static int factorial(int n) {

        if (n<0) {
            throw new IllegalArgumentException(Integer.toString(n));
        }

        int result = 1;

        while (n > 1) {
            result = result * n;
            // n = n - 1;
        }
        
        return result;

    }

    public static void main(String[] args) {

        System.out.println(factorial(10));
        
    }

}

// > java FactorialIter