本实例实现了银行业务的模拟。假设某个银行有4个窗口对外接待客户。从早晨银行开门 不断有客户进入银行。由干每个窗口在某-时刻只能接待一个客户，因此在客户人数众多时需 在每个窗口前顺次徘队。对子刚进入银行的客户，如果某个窗口的业务员正空闲，则可上前办 理、Ik务，反之，若4个窗口都忙着，则要选择一个最短的队伍排队。现在需要编制一个程序来 模拟银行的这种业务活动并计算一天中客户在银行的平均逗留时间。-The examples of simulation of the banking business. Suppose a bank of four windows external reception customers. Open the door from the morning bank customers into the bank. Dry each window in a- time only receive a customer, need a large number of customers in each window before sequentially irresolute team. The pair just entering the bank' s customer, if a window salesman is idle, you can front handle, Ik Service Conversely, if the four windows are busy, they have to choose a shortest team line up. Now need to prepare a program to simulate the banks of this business activities and calculate the average length of stay of the day the customer in the bank.