using System;

public class Program

{

    public static void Main()

    {

        A a =new A();

        B b =new B();

        C c = new C();

        Console.WriteLine(a.Hola());

        Console.WriteLine(b.Hola());

        Console.WriteLine(c.Hola());

    }

    public class A

    {

        public string Hola()

        {

            return "HOLA desde A";

        }

        public virtual string Chau()

        {

            return "CHAU desde A";

        }

    }

    public class B : A

    {

        public new string Hola()

        {

            return "HOLA desde B";

        }

    }

    public class C : A

    {

        public new string Hola()

        {

            return "HOLA desde C";

        }

    }

}