main = do
    cs <- reverse <$> getLine
    print $ solve cs (length cs)

solve :: String -> Int -> Int
solve cs n = f 0 (-1) (-1) (-1) where
    f i c w1 w2
        | i == n            = c
        | iscww             = f (i + 1) (i - w2 + 1) w1 w2
        | cs !! i == 'w'    = f (i + 1) c i w1
        | otherwise         = f (i + 1) c w1 w2
        where
            cww = (i - w2 + 1)
            iscww = cs !! i == 'c' && w2 /= -1 && (c == -1 || c > cww)