using System;

public class Program

{

    public static void Main()

    {

        CarService carService = new CarService(new VacuumService());

        carService.DoService();

        Console.WriteLine("------------------");

        carService = new CarService(new WashService());

        carService.DoService();

    }

    public class CarService{

        IService Service;

        public CarService(IService service){

            Service = service;

        }

        public void DoService(){

            Service.Service();

        }

    }

    public interface IService{

        void Service();

    }

    public class VacuumService:IService{

        public void Service(){

            Console.WriteLine("Vacuum Service");

        }

    }

    public class WashService:IService{

        public void Service(){

            Console.WriteLine("Wash Service");

        }

    }

}