private void btnDecrypt_Click(object sender, EventArgs e)
 {
     if (_inverseKeyMatrix != null)
     {
         outputTextBox.Text = MergeEncryptAndOriginalStrings(HillEncoder.Encrypt(outputTextBox.Text, _inverseKeyMatrix), outputTextBox.Text);
     }
 }
        private void btnGuessMatrixOfKey_Click(object sender, EventArgs e)
        {
            var matrixOfKey = HillEncoder.CalculateMatrixOfKey(inputTextBox.Text, outputTextBox.Text, _matrixSize);

            MessageBox.Show(matrixOfKey.Transpose().ToMatrixString(_matrixSize, _matrixSize));
        }