using System;
using static System.Console;
public class Program {
public static void Main() {
WriteLine("123456789".Right(4));
}
}
namespace System {
public static class StringExtensions {
public static string Right(this string texto, int length) => texto.Substring(texto.Length - length);
}
}
//https://pt.stackoverflow.com/q/349829/101
dXNpbmcgU3lzdGVtOwp1c2luZyBzdGF0aWMgU3lzdGVtLkNvbnNvbGU7CgpwdWJsaWMgY2xhc3MgUHJvZ3JhbSB7CglwdWJsaWMgc3RhdGljIHZvaWQgTWFpbigpIHsKCQlXcml0ZUxpbmUoIjEyMzQ1Njc4OSIuUmlnaHQoNCkpOwoJfQp9CgpuYW1lc3BhY2UgU3lzdGVtIHsKICAgIHB1YmxpYyBzdGF0aWMgY2xhc3MgU3RyaW5nRXh0ZW5zaW9ucyB7CiAgICAgICAgcHVibGljIHN0YXRpYyBzdHJpbmcgUmlnaHQodGhpcyBzdHJpbmcgdGV4dG8sIGludCBsZW5ndGgpID0+IHRleHRvLlN1YnN0cmluZyh0ZXh0by5MZW5ndGggLSBsZW5ndGgpOwogICAgfQp9CgovL2h0dHBzOi8vcHQuc3RhY2tvdmVyZmxvdy5jb20vcS8zNDk4MjkvMTAx