using System;

public class Program

{

    public static void Main()

    {

        ThirdLightExtension.Controller.SayYourName();

        Extension._controller.SayYourName();

    }

}

​

public class Extension

{

    public static IDAMController _controller;

}

​

public class ThirdLightExtension: Extension

{   

    public static IDAMController Controller

    {

        get

        {

            if (_controller == null)

            {

                _controller = new OneDAM(("Prvni DAM"));

            }

            return _controller;

        }

    }

}

​

​

​

public class OneDAM: DAMController

{

    public OneDAM(string name): base(name)

    {

    }

}

public class TwoDAM: DAMController

{

    public TwoDAM(string name): base(name)

    {

    }

}

​

public interface IDAMController

{

    void SayYourName();

}

​

public class DAMController: IDAMController

{

    public string Name;

    public DAMController(string name)

    {

        Name = name;

    }

    public void SayYourName()

    {

        Console.WriteLine(Name);

    }

}