public void LetterCasePermutation_3()
        {
            var solution = new _0784_LetterCasePermutation();
            var result   = solution.LetterCasePermutation("12345");

            AssertHelper.AssertList(new string[] { "12345" }, result);
        }
        public void LetterCasePermutation_1()
        {
            var solution = new _0784_LetterCasePermutation();
            var result   = solution.LetterCasePermutation("a1b2");

            AssertHelper.AssertList(new string[] { "a1b2", "a1B2", "A1b2", "A1B2" }, result);
        }
        public void LetterCasePermutation_2()
        {
            var solution = new _0784_LetterCasePermutation();
            var result   = solution.LetterCasePermutation("3z4");

            AssertHelper.AssertList(new string[] { "3z4", "3Z4" }, result);
        }