using System;

using System.Collections.Generic;

​

interface IHerbivore

{

    void Feed();

}

​

interface ICarnivore

{

    void Feed();

}

​

abstract class Animal

{

    public int Age {get;set;}

}

abstract class Mammal : Animal

{

    public abstract void FeedWithMilk();

}

abstract class Insect : Animal

{

    public bool HasWings {get; set;}

}

class Wolf : Mammal, ICarnivore

{

    public override void FeedWithMilk()

    {

        Console.WriteLine("Wolf's nipples");

    }

    public void Feed() 

    {

        Console.WriteLine("Wolf chews meet");

    }

}

class Cow : Mammal, IHerbivore

{

    public override void FeedWithMilk()

    {

        Console.WriteLine("Cow's nipples");

    }

    public void Feed() 

    {

        Console.WriteLine("Cow chews grass");

    }

}

class Butterfly : Insect,  IHerbivore

{

    public void Feed() 

    {

        Console.WriteLine("Butterfly chews grass");

    }

}

class Dragonfly : Insect, ICarnivore

{

    public void Feed() 

    {

        Console.WriteLine("Dragonfly chews meet");

    }

}

​

class Hedgehog : Animal, IHerbivore, ICarnivore

{

    void IHerbivore.Feed()

    {

        Console.WriteLine("Hedgehog chews grass");

    }

    void ICarnivore.Feed()

    {

        Console.WriteLine("Hedgehog chews meet");

    }

    //public void Feed()

    //{

    //  Console.WriteLine("Hedgehog chews meet or grass");

    //}

}

​

public class Program

{

    public static void Main(object [] prms)

    {

        var animals = new List<Animal>

        {

            new Cow(),

            new Butterfly(),

            new Cow(),

            new Wolf(),

            new Dragonfly(),

            new Hedgehog()

        };

        foreach(var animal in animals)

        {

            if(animal is ICarnivore)

            {

                ICarnivore carnivore = (ICarnivore)animal;

                carnivore.Feed();

            }

        }

    }

}