public void Should_Pass_Cases(int[] input, int expected)
        {
            // Arrange
            var obj = new FindDuplicateInArray();

            // Act
            var actual = obj.repeatedNumber(input.ToList());

            // Assert
            actual.Should().Be(expected);
        }
        public void Test2()
        {
            var problem = new FindDuplicateInArray();
            var input   = new List <int> {
                1, 3, 3, 3
            };
            var expectedOutput = 3;
            var output         = problem.Solve(input);

            Assert.AreEqual(expectedOutput, output);
        }