java的阶乘

package lianxi;


public class bb {
    
    public static long cal(int i){
        if (i == 1|| i==0)
            return 1;
        else
            return cal(i-1) * i;
    }
 
    public static void main(String[] argv){
        System.out.println(bb.cal(4));
    }
 
}