public void ConstructorTest()
        {
            IQueue <int> queue = new ResizingArrayQueue <int>();

            Assert.IsTrue(queue.IsEmpty());
            Assert.AreEqual(0, queue.Size());
            Assert.IsTrue(string.IsNullOrWhiteSpace(queue.ToString()));
        }
        public void ToStringTest()
        {
            IQueue <int> queue = new ResizingArrayQueue <int>();

            for (int i = 0; i < 10; i++)
            {
                queue.Enqueue(i);
            }
            Assert.AreEqual("0 1 2 3 4 5 6 7 8 9", queue.ToString());
        }