using System;

​

public interface IHandler

{

    string Handle(string message);

}

​

public class LibraryHandler : IHandler

    {

        public string Handle(string message)

        {

            throw new NotImplementedException();

        }

​

    }

​

public class Program

{

    public static void Main()

    {

        IHandler handler = new LibraryHandler();

        while (true)

        {

​

            var input = Console.ReadLine();

            Console.WriteLine(handler.Handle(input));

        }

    }

}