fun readStr () =
    let
        fun scan reader stream = SOME (StringCvt.splitl (not o Char.isSpace) reader (StringCvt.skipWS reader stream))
    in
        valOf (TextIO.scanStream scan TextIO.stdIn)
    end


exception BadInput
fun findAns s =
    let
        fun chars2Int [] acc = (acc, [])
          | chars2Int (h::tl) acc =
            if h = #"*" orelse h = #"+"
            then (acc, h::tl)
            else chars2Int tl (acc * 10 + (Char.ord h - Char.ord #"0"))

        fun findAnsAux [] acc = acc
          | findAnsAux (operatorCh :: l) acc =
            let
                val (operand, rest) = chars2Int (List.tl l) (Char.ord (List.hd l) - Char.ord #"0")
            in
                if operatorCh = #"*"
                then findAnsAux rest (acc + operand)
                else findAnsAux rest (acc * operand)
            end
                
        val ch_s = String.explode s
        val (firstVal, restChs) = chars2Int (List.tl ch_s) (Char.ord (List.hd ch_s) - Char.ord #"0")
    in
        findAnsAux restChs firstVal
    end


val () =
    let
        val s = readStr ()

        val ans = findAns s
    in
        print (Int.toString ans ^ "\n")
    end