object HelloScala {
  def main(args: Array[String]): Unit = {
    val S = io.StdIn.readLine().split("").map(_.toInt)

    var ans = 0

    for(e <- S) {
      e match {
        case 0 => ans += 10
        case _ => ans += e
      }
    }

    println(ans)
  }

}