private void timer1_Tick(object sender, EventArgs e)
        {
            int value = int.Parse(label4.Text);
            value++;
            label4.Text = value.ToString();
            String text = label3.Text;
            char firstChar = text[text.Length-1];
            text = text.Substring(0, text.Length - 1);
            label3.Text = firstChar + text;
        }













