假设某银行有四个窗口对外接待客户，从银行开门起就不断的有客户进入银行。由于每个窗口在某时刻只能接待一个客户，因此在客户众多时需按先后顺序排队，设计一个程序，遵循先到者先办理的原则，模拟银行办理业务的效率最高，客户耗时最少的情形。-Suppose there are four windows of a bank receiving external customers, starting from the bank have continued to open the door into the bank of a customer. Since each window in a certain time only to receive a customer, so the customer when there are many basis having the order line, design a program to follow the principle of first come first served processing to simulate the most efficient bank operations, customer and time-consuming the least circumstances.