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


val () =
    let
        val s = readStr ()
        val ans =
            List.foldl (fn (ch, acc) =>
                           let
                               val nTemp = Char.ord ch - Char.ord #"0"
                               val n = if nTemp = 0 then 10
                                       else nTemp
                           in
                               n + acc
                           end)
                       0
                       (String.explode s)
    in
        print (Int.toString ans ^ "\n")  
    end