using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
using System.Diagnostics;
using System.Threading;
using System.ComponentModel;
using System.Collections;
using System.Net;
using System.Runtime.Serialization;
using System.Xml;
using System.Globalization;
using System.Text.RegularExpressions;
using System.Data;
using System.Data.SqlClient;
namespace ConsoleApp
{
 /// <summary>
 /// 線程控制隊列
 /// Semaphore類
 /// </summary>
 class Program
 {
  static Semaphore semaphore;
  static void Main(string[] args)
  {
   semaphore = new Semaphore(0, 2);
   Thread thread;
   for (int i = 0; i <= 5; i++)
   {
    thread = new Thread(new ParameterizedThreadStart(Run));
    thread.Start("thread_"+i.ToString());
   }
   semaphore.Release(2);
   Console.ReadLine();
  }
  static void Run(object obj)
  {
   semaphore.WaitOne();
   Console.WriteLine("thread " + obj.ToString() + " into the method");
   System.Threading.Thread.Sleep(5000);   
   Console.WriteLine("_thread " + obj.ToString() + " leave the method");
   semaphore.Release();
  }
 }
}