TestAB 2

class A7 {
    int ax = 10;
    int ay = 20;
}

class B7 extends A7 {
    int bx = 30;
    int by = 40;
}

public class TestAB {
    public static void main(String[] args) {
        B7 b = new B7();
        A7 a = new B7();
        System.out.println("B7: " + b.bx + ": " + b.by);
        System.out.println("A7: " + a.ax + ": " + a.ay);
        b.bx = 5;
        b.by = 6;
        System.out.println("B7: " + b.bx + ": " + b.by);
        System.out.println("A7: " + a.ax + ": " + a.ay);
    }
}