//Calletz
        private void ButtonCheckCollatz_Click(object sender, EventArgs e)
        {
            if (Int32.TryParse(textBoxNumber.Text, out x) && Int32.Parse(textBoxNumber.Text) != 0)
            {
                Calletz calletz = new Calletz();

                textBoxCollatz.Text = calletz.CheckCalletz(Int32.Parse(textBoxNumber.Text));
            }
            else
            {
                textBoxCollatz.Text = "Input number";
            }
        }
        private void CheckLongestCalletz_Click(object sender, EventArgs e)
        {
            Calletz calletz = new Calletz();

            textBoxLongestChain.Text = calletz.CheckLongestCalletzUnderMilion();
        }