银行柜员服务问题:银行有n个柜员负责为顾客服务，顾客进入银行先取一个号码，然后等着叫号。当某个柜员空闲下来，就叫下一个号。

　　编程实现该问题，用P、V操作实现柜员和顾客的同步。

实现要求

某个号码只能由一名顾客取得；

不能有多于一个柜员叫同一个号；

有顾客的时候，柜员才叫号；

无柜员空闲的时候，顾客需要等待；

无顾客的时候，柜员需要等待。

测试文本格式

　　测试文件由若干记录组成，记录的字段用空格分开。记录第一个字段是顾客序号，第二字段为顾客进入银行的时间，第三字段是顾客需要服务的时间。

输出要求

　　对于每个顾客需输出进入银行的时间、开始服务的时间、离开银行的时间和服务柜员号。-Bank teller service issues: bank teller is responsible for the n-th customer service, the customer enters the bank to take a number and wait for call number. When a teller idle down, and called the next number. Programming the issue, P, V synchronization teller operations and customers. Implementation requires a number can only be achieved by a customer　can not have more than one teller called the same number　has a customer when the teller called number　without teller idle time, the customer need to wait　without the customer' s time, the teller need to wait. Test text test file composed by a number of records, record fields separated by a space. Record first field is the customer number, the second field is the time a customer enters the bank, and the third field is the time the customer needs the service. Output requirements for each customer need output into the bank' s time to begin serving time, leaving the bank teller time and service number.