import Data.Char
main = getLine >>= putStrLn . solve

solve :: String -> String
solve xs = fst $ foldr ff ([], m) xs
	where
	m = length xs
	ff x (acc, n)
		| ord x - n < ord 'A' = ((chr $ ord 'Z' - ord x + n  - 1 + ord 'A') : acc, n - 1)
		| otherwise = ((chr $ ord x - n) : acc, n - 1)