Stack(Push and Pop)

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Linq;

using System.Text;

using System.Windows.Forms;

namespace WindowsFormsApplication1

{

    public partial class stack : Form

    {

        public stack()

        {

            InitializeComponent();

        }

        Stack<int> st = new Stack<int>();

        private void btnpush_Click(object sender, EventArgs e)

        {

            st.Push(Convert.ToInt32(textBox1.Text));

            listBox1.Items.Add(textBox1.Text);

            textBox1.Text = "";

        }

        private void btnpop_Click(object sender, EventArgs e)

        {

            int i = st.Pop();

            MessageBox.Show(i + "is poped");

            int k = st.Count;

            listBox1.Items.RemoveAt(k);

            listBox1.Refresh();

        }

    }

}