Program to show single inheritance in java

class am
{
public void show()
{
System.out.print("\nshow");
}
}
class B extends am
{
public void in()
{
System.out.print("\nin");
}
}

public class Aaa {

public static void main(String[] args) {

am m=new am();
B n=new B();
m.show();
n.in();
n.show();
}
}
output:

show
in
show