public void Test1()
        {
            int rectangles = NumberOfRectanglesInGrid.NumberOfRectangles(4, 4);

            Assert.AreEqual(100, rectangles);
        }
        public void Test2()
        {
            int rectangles = NumberOfRectanglesInGrid.NumberOfRectangles(5, 5);

            Assert.AreEqual(225, rectangles);
        }