var urls = new ConcurrentQueue<string>(Directory.GetFiles(@"C:\Windows\System32"));
            var total = urls.Count;
            var tasks = new Task[20];
            var rand = new Random();
 
            for (int i = 0; i < tasks.Length; i++)
            {
                tasks[i] = new Task(() =>
                {
                    string url;
 
                    while (urls.TryDequeue(out url))
                    {
                        Console.WriteLine(url);
                        Thread.Sleep(1000 + rand.Next(4000));
                    }
                });
            }
 
            var prog = Task.Factory.StartNew(() =>
            {
                foreach (var t in tasks)
                {
                    t.Start();
                }
 
                while (!Task.WaitAll(tasks, 1000))
                {
                    Console.WriteLine(100 * urls.Count / total);
                }
            });
 
            prog.Wait();

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