C++之线程信号量机制

#include<iostream>
#include<Windows.h>
using namespace std;
int tickets=100;         //火车票总数
HANDLE hSemaphore;
DWORD WINAPI Thread1Proc(LPVOID lpParameter);//进程函数
DWORD WINAPI Thread2Proc(LPVOID lpParameter);//进程函数
void main()
{
	HANDLE hThread1;
	HANDLE hThread2;
	hThread1=CreateThread(NULL,0,Thread1Proc,NULL,0,NULL);   //创建线程
	hThread2=CreateThread(NULL,0,Thread2Proc,NULL,0,NULL);
	hSemaphore=CreateSemaphore(NULL,1,1,NULL);      //创建信号量，初始为1，最多为1
	CloseHandle(hThread1);       //释放句柄
	CloseHandle(hThread2);
	CloseHandle(hSemaphore);
	while(TRUE)
	{
		WaitForSingleObject(hSemaphore,INFINITE);
		if(tickets>0)
		{
			cout<<"主线程卖出第"<<tickets--<<"张票"<<endl;
			Sleep(50);
			ReleaseSemaphore(hSemaphore,1,NULL);
		}
		else
		{
			ReleaseSemaphore(hSemaphore,1,NULL);      //释放信号量资源
			break;
		}
	}
	ExitThread(0);
}
DWORD WINAPI Thread1Proc(LPVOID lpParameter)
{
	while(TRUE)
	{
		WaitForSingleObject(hSemaphore,INFINITE);//申请信号量
	    if(tickets>0)
	    {
		   cout<<"线程一卖掉第"<<tickets--<<"张票"<<endl;
		   Sleep(50);
		   ReleaseSemaphore(hSemaphore,1,NULL);
	    }
	    else
		{
			ReleaseSemaphore(hSemaphore,1,NULL);
			break;
		}
	}
	return 0;
}
DWORD WINAPI Thread2Proc(LPVOID lpParameter)
{
	while(TRUE)
	{
		WaitForSingleObject(hSemaphore,INFINITE);
		if(tickets>0)
		{
			cout<<"线程二卖出第"<<tickets--<<"张票"<<endl;
			Sleep(50);
			ReleaseSemaphore(hSemaphore,1,NULL);
		}
		else
		{
			ReleaseSemaphore(hSemaphore,1,NULL);
			break;
		}
	}
	return 0;
}