count e l = h e l 0
            where h e [] n = n
                  h e (car:cdr) n = if e == car then h e cdr (n+1) else h e cdr n

solve :: String -> [Int]
solve w = do c <- w
             return (count c w)

getAns :: [Int] -> String
getAns [] = "Yes"
getAns (e:es) = if even e then getAns es else "No"

main = do
  w <- getLine
  putStrLn $ getAns $ solve w
