extend Inheritance

public class SimpleInheritance {
public static void main(String arr[]) {
A superOb = new A();
B subOb = new B();

superOb.i = 10;
superOb.j = 20;
System.out.println("Contents of superOb:");
superOb.showij();
System.out.println();


subOb.i = 7;
subOb.j = 8;
subOb.k = 9;

System.out.println("Contents of subOb:");
subOb.showij();
subOb.showk();
System.out.println();

System.out.println("Sum of i, j, and k in subOb:");
subOb.sum();

}
}

class A {
int i, j;

void showij() {
System.out.println("i and j: " + i + ", " + j);
}
}

class B extends A {
int k;

void showk() {
System.out.println("k: " + k);
}

void sum() {
System.out.println("i + j + k: " + (i + j + k));
}
}