public void SwapExample()
        {
            var vector1 = new Vector2D(1, 2);

            var vector2 = new Vector2D(3, 4);

            vector1.Swap(vector2);

            Assert.AreEqual(3, vector1.X);
            Assert.AreEqual(4, vector1.Y);
            Assert.AreEqual(1, vector2.X);
            Assert.AreEqual(2, vector2.Y);
        }