object WorkingWithLists extends App {

  import scala.io.StdIn.readLine

  val input:List[String] = readLine().split(",").map(x => x.trim()).toList

  def list(list: List[String]) = list foreach println
  def maxLength(list: List[String]) = println(list.reduce((a,b) => if(a.length>=b.length) a else b))
  def averageLength(list: List[String]) = {
    val average = list.map(x => x.length.asInstanceOf[Double]).reduce((a,b) => a+b)/list.length
    println(f"$average%2.1f")
  }

  def askForCommand():Unit = {
    val command = readLine() match {
      case "list" => list(input); askForCommand()
      case "maxLength" => maxLength(input); askForCommand()
      case "averageLength" => averageLength(input); askForCommand()
      case "exit" =>
      case _ => println("unknown command"); askForCommand()
    }
  }

}