/**
*************************************************
  Skrá: T203Sd4_3.cs
  Höfundur: Ragnar Geir Brynjólfsson.
  Dagsetning: 06.06.2005.
  Stafli útfærður með Stack
*************************************************
*/
using System;
using System.Collections;
class MyStackException : SystemException {
  public MyStackException(string err):base(err) {}
}
class MyStack {
  private const int MAX = Int32.MaxValue;
  private Stack S = new Stack();
  private int topp = -1;
  public int size(){
    return topp+1;
  }
  public bool isEmpty(){
    return (topp<0);
  }
  public bool isFull() {
    return (S.Count==MAX);
  }
  public Object top() {
    if(isEmpty())
       throw new MyStackException("Stafli tómur.");
    return S.Peek();
  }
  public void push(Object o) {
    if (isFull())
       throw new MyStackException("Stafli fullur.");
    S.Push(o);
    topp++;        
  }
  public Object pop() {
    if(isEmpty()) 
       throw new MyStackException("Stafli tómur.");
    topp--;
    return S.Pop();
  }
  public override string ToString() {
    String utstr="[ ";
    IEnumerator me = S.GetEnumerator();
    while(me.MoveNext())
      utstr+=me.Current.ToString()+" ";
    utstr+="]";
    return utstr;
  }
}
class T203Sd4_3 {
  static void Main() {
    MyStack s = new MyStack();
    s.push(1.23);
    s.push(2.14);
    Console.WriteLine(s.ToString());
    Console.WriteLine(s.pop());
    Console.WriteLine(s.pop());
  }
}