using System;
using System.Collections.Generic;
 
namespace Polymorphism
{
    class Program
    {
 
        public class Car
        {
            public string Drive()
            {
                return "Wrrrr!";
            }
        }
 
        public class Dog 
        {
            public string Talk()
            {
                return "Woof";
            }
        }
 
        static void Main()
        {
            var car = new Car();
            var dog = new Dog();
 
	List<object> list = new List<object>();
	list.Add(car);
	list.Add(dog);

	foreach (object o in list)
	{
		if (o is Car) 
			Console.WriteLine((o as Car).Drive());
		else
			Console.WriteLine((o as Dog).Talk());
	}

        }
    }
}