-- yukicoder My Practice
-- author: Leonardone @ NEETSDKASU


main = print . flip f (\x -> x) =<< getLine where
    f xs g =
        case ys of
            []       -> g v
            ('+':zs) -> f zs $ (* g v)
            ('*':zs) -> f zs $ (+ g v)
        where
            p c = c == '+' || c == '*'
            (n, ys) = break p xs
            v = read n