说明：  用多线程实现“生产者-消费者问题”本作业要求设计并实现一个进程，该进程拥有一个生产者线程和一个消费者线程，它们使用N个不同的缓冲区（N为一个自定义的确定的数值，例如N=32）。你需要使用如下信号量：一个互斥信号量，用以阻止生产者线程和消费者线程同时操作缓冲区列表；一个信号量，当生产者线程生产出一个物品时可以用它向消费者线程发出信号；一个信号量，消费者线程释放出一个空缓冲区时可以用它向生产者线程发出信号；
(Achieved with multi-threaded " producer- consumer problems" of the operational requirements of the design and implementation of a process that has a producer thread and a consumer thread, which use different buffer N (N is a custom to determine values, for example, N = 32). The amount you need to use the following signals: a mutex to prevent the producer and consumer threads simultaneously thread the buffer list a signal to the amount produced when the producer thread can use an item when sent to the consumer thread signal a semaphore, the consumer thread to release an empty buffer when the producer thread can use it to send a signal )