using System;

public class Animal

{

    public virtual void MakeNoise()

    {

        Console.WriteLine("Making noise...");

    }

}

​

public class Dog : Animal

{

    public override void MakeNoise()

    {

        Console.WriteLine("Barking...");

    }

}

​

public class MainClass

{

    public static void Main()

    {

        Animal animal = new Animal();

        animal.MakeNoise();

​

        Dog dog = new Dog();

        dog.MakeNoise();    

    }

}