public void addReturnsInt()
        {
            var stringCalculator = new stringCalculator();
            var add = stringCalculator.Add("0");

            Assert.IsInstanceOfType(add, typeof(int));
        }
        public void allowMultpleDelimiters()
        {
            var       stringcalculator = new stringCalculator();
            var       add            = stringcalculator.Add("//[*][%]\n1*2%3");
            const int expectedResult = 6;

            Assert.AreEqual(expectedResult, add);
        }
        public void anyLenghtDelimters()
        {
            var       stringcalculator = new stringCalculator();
            var       add            = stringcalculator.Add("//[***]\n1***2***3”");
            const int expectedResult = 6;

            Assert.AreEqual(expectedResult, add);
        }