public void Add1WithTwoNumbersArgumentTestMethod()
        {
            const string numbers  = "62,800";
            const int    expected = 862;

            int actual = StringCalculator.Add1(numbers);

            Assert.AreEqual(expected, actual);
        }
        public void Add1WithSingleNumberArgumentTestMethod()
        {
            const string numbers  = "64";
            const int    expected = 64;

            int actual = StringCalculator.Add1(numbers);

            Assert.AreEqual(expected, actual);
        }