import Control.Applicative ((<$>))
import Data.ByteString.Char8 (ByteString)
import qualified Data.ByteString.Char8 as B

main :: IO ()
main = solve <$> B.getLine >>= print

solve :: ByteString -> Int
solve = snd . B.foldr f (0, 0)
  where f x (w, cww) | x == 'w' = (w+1, cww)
                     | x == 'c' = (w, comb w 2 + cww)
                     | otherwise = (w, cww)

comb n m | n < m = 0
         | m == 0 || n == m = 1
         | otherwise = comb (n-1) (m-1) * n `div` m