static void Test(IMyQueue <int> queue) { foreach (int i in Enumerable.Range(0, 9)) { queue.Enqueue(i); } Console.WriteLine(queue.Dequeue()); Console.WriteLine(queue.Peek()); foreach (int i in Enumerable.Repeat(2, 5)) { queue.Enqueue(i); } try { while (true) { Console.WriteLine(queue.Dequeue()); } } catch (InvalidOperationException) { Console.WriteLine("Queue is empty"); } }