时钟提供接听电话服务的时间（以分钟计），然后这个时钟将循环地自增1（分钟）

直到到达指定时间为止。在时钟的每个“时刻”，就会执行一次检查来看看当前电话的服务

是否已经完成了，如果是，这个电话从电话队列中删除，模拟服务将从队列中取出下一个电

话（如果有的话）继续开始。同时还需要执行一个检查来判断是否有一个新的电话到达。如

果是将其到达时间记录下来，并为其产出一个随机服务时间，这个服务时间也被记录下来，

然后这个电话被放入电话队列中，当客户服务人员空闲时，按照先来先服务的方式处理这个

队列。当时钟到达指定时间时，不会再接听新电话，但是服务将继续，直到结束当前服务。-Clock time (in minutes) to answer the phone services, then the clock will cycle to increment a (minutes) until the specified time is reached. In each " moment"　of the clock will run a check to see current phone service has been completed, if the phone is removed from the telephone queue, analog service will remove from the queue the next phone (if there is words) to continue to start. Also need to perform an inspection to determine whether there is a new phone arrives. Its arrival time recorded, and its output is a random service time, the service time is also recorded, then this phone into the phone queue, when the customer service staff is idle, according to a first-come, first serve The way to deal with this queue. When the clock reaches the specified time, no longer answer the new call, but the service will continue until the end of the current service.