using System;

​

    public class Origin

    {

    public class A  

{

    public void F()

    {

    Console.WriteLine("A.F");

   }

}

     public class B:A

{   

    public void G()

    {

    Console.WriteLine("B.G");

}

}

​

​

​

    public static void main()

    {

    B b=new B();

    b.F();//Inherited from A

    b.G();//Introduced in B

    Console.ReadLine();

 }

}   

​