import Data.Char (ord)

chars = cycle ['A' .. 'Z']

encode = map (subtract (ord 'A') . ord)

decode = map (chars !!)

usa s = decode $ zipWith (\n c -> f (c - n)) [1 ..] $ encode s
  where
    f a
      | a < 0 = (26 * 1024) + a
      | otherwise = a

main = getLine >>= putStrLn . usa