线程1：临界区，解决线程访问冲突问题

#define   N 64
int num = 0;
CRITICAL_SECTION cs1;
CRITICAL_SECTION cs2;//定义临界区，结构体变量
DWORD WINAPI  add(void *p)
{
	EnterCriticalSection(&cs1);
	for (int i = 0; i < 100000;i++)
	{
		num++;
	}
	LeaveCriticalSection(&cs1);
	return 0;
}
DWORD WINAPI  sub(void *p)
{
	EnterCriticalSection(&cs2);
	for (int i = 0; i < 100000; i++)
	{
		num--;
	}
	LeaveCriticalSection(&cs2);
	return 0;
}
//临界区  用于解决线程冲突
void main()
{
	InitializeCriticalSection(&cs1);//初始化
	InitializeCriticalSection(&cs2);//初始化
	{
		HANDLE hd[N];
		for (int i = 0; i < N; i++)
		{
			hd[i] = CreateThread(NULL, 0, add, NULL, 0, NULL);//创建线程
		}
		WaitForMultipleObjects(N, hd, TRUE, INFINITE);//等待全部线程退出
		printf("num=%d\n", num);
	}
	{
		HANDLE hd[N];
		for (int i = 0; i < N; i++)
		{
			hd[i] = CreateThread(NULL, 0, sub, NULL, 0, NULL);//创建线程
		}
		WaitForMultipleObjects(N, hd, TRUE, INFINITE);//等待全部退出
		printf("num=%d", num);
	}
	DeleteCriticalSection(&cs1);//释放
	DeleteCriticalSection(&cs2);//释放
	system("pause");
}