using System;

public class Polymorphism

{

    public static void Main()

    {

        MakeItSpeak(new Dog());

        MakeItSpeak(new Cat());

        MakeItSpeak(new George());

    }

    public static void MakeItSpeak(Animal animal)

    {

        string message = animal.MakeNoise();

        Console.WriteLine(message);

    }

    public abstract class Animal {

        public abstract string MakeNoise();

    }

​

    public class Dog

        : Animal

    {

        public override string MakeNoise() => "Woof";

    }

​

    public class Cat

        : Animal

    {

        public override string MakeNoise() => "Hiss";

    }

​

    public class George

        : Animal

    {

        public override string MakeNoise() => "Buh";

    }

}