using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace WindowsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            Stack days = new Stack();
            days.Push("SunDay");
            days.Push("MonDay");
            days.Push("TueDay");
            days.Push("WedDay");
            days.Push("ThuDay");
            days.Push("FriDay");
            days.Push("SaturDay");
            if (days.Count ==7)
            {
                MessageBox.Show(days.Pop().ToString ());
            }
            else
            {
                MessageBox.Show("SaturDay does not exist");
            }
        }
    }
}