using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

public class Program

{

    public static void Main()

    {   

        Thebegin:

        Console.WriteLine("Bitte geben Sie einen Command ein");

        string command = Console.ReadLine();

            if (command == "verschlüsseln")

            {

            int key = 5;

            Console.WriteLine("Bitte geben Sie den zu verschlüsselnden Text ein");

            string text = Console.ReadLine();

            int l = text.Length;

            string endtext = null;

            for (int i = 0; i < l; i++)

                {

                char ch = text.ElementAt(i);

                int asciich = (int) ch;

                int step1 = asciich + key;

                char vers = (char) step1;

                endtext = endtext + vers;

                }

            Console.WriteLine(endtext); 

            goto Thebegin;

            }

            else if (command == "entschlüsseln")

                {

                Console.WriteLine("Bitte geben Sie den zu entschlüsselnden Text ein");

                string vstring = Console.ReadLine();

                int ekey = 5;

                string estring = null;

                int z = vstring.Length;

                for (int j=0; j < z; j++)

                    {

                        char ch = vstring.ElementAt(j);

                        int asciich = (int) ch;

                        int echar = asciich - ekey;

                        estring = estring + (char) echar;

                    }

                Console.WriteLine(estring);

                goto Thebegin;

                }

            else

                {

                Console.WriteLine("Command not found");

                goto Thebegin;

                }

        }

}