public void Should_replace_space_by_percent20(string input, string ExpectedResult)
        {
            var arr    = input.ToCharArray();
            var result = new Q1_03_URLify().URLify(arr, input.Trim().Length);

            Assert.AreEqual(result, ExpectedResult);
        }
        //[TestCase("Mr John Smith", "Mr%20John%20Smith")]
        //[TestCase("Mr John Smith   ", "Mr%20John%20Smith")]
        //[TestCase("abc", "abc")]
        //[TestCase("ab c", "ab%20c")]
        //[TestCase(" ", "%20")] // Failed
        //[TestCase(null, null)] // Failed
        public void Should_Replace_space_by_percent20(string input, string expected)
        {
            string result = new Q1_03_URLify().UrlifySpace(input.Trim());

            Assert.That(result, Is.EqualTo(expected));
        }