using System;

using System.Collections.Concurrent;

using System.Linq;

using System.Threading;

​

public class Program

{

    static ConcurrentDictionary<int, string> _concurrent = new ConcurrentDictionary<int, string>();

​

    public void Main()

    {

        Thread thread1 = new Thread(() => A("1",2));

        Thread thread2 = new Thread(() => A("2",3));

        thread1.Start();

        thread2.Start();

        thread1.Join();

        thread2.Join();

        Console.WriteLine("Total: {0}", _concurrent.Count());

        Console.WriteLine("--------------------");

        _concurrent.TryAdd(1, "Teste");

        foreach(var item in _concurrent)

        {

            Console.WriteLine("Key: {0} | Value: {1}", item.Key, item.Value);

        }

        Console.WriteLine("Sucesso: {0}", _concurrent.TryAdd(31, "Teste"));

        Console.WriteLine("Sucesso: {0}", _concurrent.TryAdd(31, "Teste"));

    }

​

    static void A(string val, int n)

    {

        for (int i = 1; i < 11; i++)

        {

            _concurrent.TryAdd(i * n, i.ToString() + " " + val);

            Thread.Sleep(TimeSpan.FromMilliseconds(100));

        }

    }

}