using System;
using System.Linq;

public class Program
{

	static void Main()
	{
		var CharList = Console.ReadLine().ToCharArray().ToList<char>();

		for (int i = 0; i < CharList.Count; i++)
		{
			Console.Write(ConverAlpha(Convert.ToInt32(CharList[i]) - (i + 1 % 26)));
		}

		Console.WriteLine();
	}


	private static char ConverAlpha(int CharCode)
	{		
		if (Convert.ToInt32('A') > CharCode)
			return ConverAlpha(CharCode + 26);


		return Convert.ToChar(CharCode);
	}
}