static void Main(string[] args)
{
CountDownLatch cdl = new CountDownLatch(10);
for (int i = 0; i < 10; i++)
{
Task t = new Task(() =>
{
Thread.Sleep(1000);
cdl.CountDown();
Console.WriteLine(cdl.GetCountDownNumber());
});
t.Start();
}
cdl.Wait();
Console.WriteLine("over");
Console.ReadLine();
}