main :: IO()
main = do
  x <- read <$> getLine
  putStrLn . show . solve $ x

solve :: Int -> String
solve x = if x > 25 || x < 22 then error "range out" else inSolve x []
  where
    inSolve :: Int -> [String] -> String
    inSolve 25 str = unwords $ "Christmas" : str
    inSolve x str = inSolve (x + 1) ("Eve" : str)
