Fatorial.java

public class Fatorial {
    public static int fatorial(int x) {
        if (x == 0)
            return 1;

        int total = x;
        for (int i = x - 1; i > 0; i--) {
            total *= i;
        }
        return total;
    }
    public static void main(String[] args) {
        System.out.println("4! = " + fatorial(4));
    }
}