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I've use the below code to implement and test a blocking queue. I test the queue by starting up 5 concurrent threads (the removers) to pull items off the queue, blocking if the queue is empty and 1 concurrent thread (the adder) to add items to the queue intermitently. However, if I leave it running for long enough I get an exception because one of the remover threads comes out of a waiting state even when the queue is empty. Does anyone know why I get the exception? Note, I'm interested in knowing why this doesn't work as opposed to a working solution (as I can just Google that). I'd greatly appreciate your help. using System; using System.Threading; using System.Collections.Generic; namespace Code { class Queue<T> { private List<T> q = new List<T>(); public void Add(T item) { lock (q) { q.Add(item); if (q.Count == 1) { Monitor.Pulse(q); } } } public T Remove() { lock (q) { if (q.Count == 0) { Monitor.Wait(q); } T item = q[q.Count - 1]; q.RemoveAt(q.Count - 1); return item; } } } class Program { static Random r = new Random(); static Queue<int> q = new Queue<int>(); static int count = 1; static void Adder() { while (true) { Thread.Sleep(1000 * ((r.Next() % 5) + 1)); Console.WriteLine("Will try to add"); q.Add(count++); } } static void Remover() { while (true) { Thread.Sleep(1000 * ((r.Next() % 5) + 1)); Console.WriteLine("Will try to remove");

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