using System;
public class Program
{
    public static void Main()
    {
        //int num = int.Parse(Console.ReadLine() ?? string.Empty);
        //string[] pass = (Console.ReadLine() ?? string.Empty).Trim().Split(' ');
        string a = Console.ReadLine() ?? string.Empty;

        string change = "";
        string alph = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
        for (int i = 0; i < a.Length; i++)
        {
            int index = alph.IndexOf(a[i]);

            if(index-(i+1) < 0)
            {
                int aa = i+1;
                while(aa > 25)
                {
                    aa -= 25;
                }
                change += alph[alph.Length - aa];
            }
            else
            {
                change += alph[index - (i + 1)];
            }
        }
        
        Console.WriteLine(change);
    }
}