using System;  

using System.Collections.Concurrent;  

using System.Threading.Tasks;  

namespace ConcurrentBag {  

    class Program {  

        static void Main(string[] args) {  

            ConcurrentBag < int > bag = new ConcurrentBag < int > ();  

            for (int i = 1; i <= 50; ++i) {  

                bag.Add(i);  

            }  

            var task1 = Task.Factory.StartNew(() => {  

                while (bag.IsEmpty == false) {  

                    int item;  

                    if (bag.TryTake(out item)) {  

                        Console.WriteLine($"{item} was picked by {Task.CurrentId}");  

                    }  

                }  

            });  

            var task2 = Task.Factory.StartNew(() => {  

                while (bag.IsEmpty == false) {  

                    int item;  

                    if (bag.TryTake(out item)) {  

                        Console.WriteLine($"{item} was picked by {Task.CurrentId}");  

                    }  

                }  

            });  

            Task.WaitAll(task1, task2);  

            Console.WriteLine("DONE");  

        }  

    }  

}