The Entrance and Exit sytem of the Library

A book detection system is installed at the door of the Library. A system detects the books which are being taken out from the Library without permission. You are expected to go through the denoted gates when you enter and leave the Library. You are free to bring any sort of personal belongings into the the Library.
You are expected to look at the bulletin board on the right of the entrance whenever you visit the Library. There you will find all sorts of notices and invitations from the Library.