// test using super

public class super1 {
    
    public static void main(String args[]) {
	
	Data2 a = new Data2(1,2);

	a.print_m();
	a.print_n();

    } // method main

} // class super1


class Data1 {
    protected int m;
    Data1(int i) {
	m = i;
    } // constructor Data1
} // class Data1

class Data2 extends Data1 {
    private int n;
    Data2(int i, int j) {
	super(i);
	n = j;
    } // construtor Data2 

    public void print_m() {
        System.out.println("m: "+m);
    } // method print_m

    public void print_n() {
        System.out.println("n: "+n);
    } // method print_n

} // class Data2

/* output:
m: 1
n: 2
*/