《操作系统概念》第七版 中的实验项目：生产者消费者问题。本程序中，main()函数需要三个参数：主线程休眠时间；生产者线程数；消费者线程数。各线程的休眠等待时间是随机的。-Experimental project in the seventh edition of the operating system concept: producers and consumers. The program, the main () function takes three parameters: the main thread sleep time　producer number of threads　consumers the number of threads. Dormant wait time for each of the threads is random.