using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

        var responseNomor = "B001";

        Console.WriteLine("Length");

        Console.WriteLine(responseNomor.Length);

        // var noAntre = responseNomor.Substring(responseNomor.Length - 2, responseNomor.Length);

        Console.WriteLine(noAntre);

        Console.ReadLine();

    }

}