import Data.Char (isDigit, digitToInt)

extractDigits :: String -> [Int]
extractDigits = extractDigits' []
    where
        extractDigits' :: [Int] -> String -> [Int]
        extractDigits' ds [] = ds
        extractDigits' ds (c : cs)
            | isDigit c = extractDigits' (digitToInt c : ds) cs
            | otherwise = extractDigits' ds cs

main :: IO ()
main = putStrLn . show . sum . extractDigits =<< getLine