邮箱问题：150个邮箱，从邮箱2开始，打开所有偶数编号邮箱的门，接着从编号3开始，每隔3个邮箱，若门关着则打开，开着则关闭，随后每隔4个重复此过程，再每隔5个重复此过程，如此下去。判断最后哪些邮箱关着-E-mail questions: 150 mailboxes from the mailbox 2 starts, open the door all the even-numbered mailbox, and then start from number three, every three