using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

    }

}

​

public interface INotificationSender<T>

{

    void Send(T notification);

}

​

public class EmailNotificationSender : INotificationSender<Email>

{

    private readonly IEmailSender _emailSender;

    public EmailNotificationSender(IEmailSender es) { _emailSender = es; }

​

    public void Send(Email notification) { _emailSender.SendEmail(notification); }

}

​

public class PushNotificationSender : INotificationSender<Push>

{

    private readonly IPushSender _pushSender;

    public PushNotificationSender(IPushSender ps) { _pushSender = ps; }

​

    public void Send(Push notification) { _pushSender.SendPush(notification); }

}

​

public interface IEmailSender { void SendEmail(Email e); }

public interface IPushSender { void SendPush(Push p); }

public class Email {}

public class Push {}