class SuperStack[T] {
  private var list: List[T] = List[T]()
  def push(x : T) {
    list = x::list
    println("hui1")
  }
  def pop(): T = list match {
    case x::list => x
    case Nil => throw new IllegalStateException("SuperStack is empty")
  }
  def empty(): Boolean = list.isEmpty
}

object SuperStack {
  implicit class SuperStackNumeric[T](stack : SuperStack[T])(implicit n: Numeric[T]) {
    private var min: List[T] = List[T]()
    private var max: List[T] = List[T]()

    def push(x : T) {
      max = x :: max
      min = x::min

      println("hui2")

      if(stack.list.isEmpty) {
        println("hui")
        max = x::max
        min = x::min
      }else {
      /*  if(stack.list.last > max.last) {
          max = stack.list.last::max
        } else {
          max = max.last::max
        }

        if(stack.list.last < min.last) {
          min = stack.list.last::min
        } else {
          min = min.last::min
        }*/
      }
      stack.list = x::stack.list
    }
    def minf() = max.size
    def maxf() = max.last
    def average(): Double = n.toDouble(stack.list.reduceRight(n.plus))/stack.list.length
  }
}