private void AddSecondLongerListsTest(IListNumbersOperator listNumbersOperator)
        {
            int        onesDigit      = 9;
            int        tensDigit      = 5;
            int        hundredsDigit  = 7;
            int        thousandsDigit = 9;
            Node <int> first          = CreateList(onesDigit, tensDigit, hundredsDigit, thousandsDigit);

            onesDigit      = 7;
            tensDigit      = 4;
            hundredsDigit  = 8;
            thousandsDigit = 8;
            int        tenThousandsDigit = 9;
            Node <int> second            = CreateList(onesDigit, tensDigit, hundredsDigit, thousandsDigit, tenThousandsDigit);

            onesDigit         = 6;
            tensDigit         = 0;
            hundredsDigit     = 6;
            thousandsDigit    = 8;
            tenThousandsDigit = 0;
            int        hundredThousandsDigit = 1;
            Node <int> expected = CreateList(onesDigit, tensDigit, hundredsDigit, thousandsDigit, tenThousandsDigit, hundredThousandsDigit);

            Node <int> result = listNumbersOperator.AddNumbers(first, second);

            AssertResult(expected, result);
        }
 private void RunTests(IListNumbersOperator listNumbersOperator)
 {
     AddEqualListsTest(listNumbersOperator);
     AddFirstLongerListsTest(listNumbersOperator);
     AddSecondLongerListsTest(listNumbersOperator);
 }