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public class A {
private int a;
public A(int a){
this.a = a;
}
public int getA(){
return this.a;
}
public int add(A a){
return this.a + a.getA();
}
public int m(){
return 1;
}
public int n(){
return this.m();
}
public String toString(){
return "Ich bin ein A.";
}
}

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public class B extends A {
private int a;
public B(int a){
super(a);
}
public int getA(){
return this.a;
}
public int add(B b){
return this.getA() + b.getA();
}
public int m(){
return 2;
}
public int n() {
return this.m();
}
public String toString(){
return "Ich bin ein B.";
}
}

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public class C {

public static String print(A a){
 return "Parameter A: " + a.toString();
 }

public static String print(B b){
 return "Parameter B: " + b.toString();
 }
 public static void main(String[] args) {

 A o1 = new A(2);
 B o2 = new B(3);
 A o3 = new B(4);



 System.out.println(o3.n());


 }
 }
 }