package method;

public class Demo4 {
    public static void main(String[] args) {
       Demo4 d= new Demo4();
       d.test(1,2,3,4);
        }


    public void test(int... i){
        System.out.println(i[2]);
    }
}

package method;

public class Demo5 {
    public static void main(String[] args){
        Demo5 test=new Demo5();
        test.test();
    }
    public void test(){
        test();
    }
}

package method;

public class Demo6 {
    public static void main(String[] args){
        System.out.println(f(7));
    }
    //n的阶层
    public static int f(int n) {
        if(n==1){
            return 1;
        }else{
            return n*f(n-1);
        }
    }
}