第十七道Java小问题

public class A {
    private int i = 1;

    protected void printi() {
        System.out.println(i);
    }

    public A() {

        printi();
        i = 0;
    }

    public static void main(String[] args) {
        new B();
    }
}

class B extends A {
    private int i = 2;

    protected void printi() {
        System.out.println(i);
    }

    B() {
        i = 3;
    }
}

 

请问以上程序的输出是：