// a little bit on class hierarchy

public class hierarchy2 {
    
    public static void main(String args[]) {
	
	System.out.println(Data121.a121);
	// System.out.println(Data121.a11); // this won't work!
	System.out.println(Data121.a12);
	System.out.println(Data121.a1);

    } // method main

} // class hierarchy2

class Data1 {
    static int a1=1;
}

class Data11 extends Data1 {
    static int a11=11;
}

class Data12 extends Data1 {
    static int a12=12;
}

class Data121 extends Data12 {
    static int a121=121;
}

/* output
121
12
1
*/