The school library is equipped with advanced anti-theft equipment (to prevent students from preventing teachers), and the entrance and exit of the stacks are equipped with alarms. Any student passing by with a book that hasn't passed through the stacks will definitely cause an alarm bell to ring and trap himself. The window of the library was also tied tightly with wire, which dashed the students' hopes of transporting books out of the window. Although the library was heavily guarded, Yang Yang and I managed to put the books we wanted on the shelves. We accidentally stole the book. On one occasion, I read a guide to electrotechnics problem-solving borrowed by Zhang Chaofan from the library. I turned to a page in the book and found a silver-white metal strip deeply inserted in the binding seam of this page. I think it's a magnetic stripe closely related to the alarm. If it is removed from the book, the alarm will be useless, so I will take the book in and out of the library. I'm excited about my bold idea. I immediately took off the magnetic stripe of this book, stuffed it in my arms and went to the library. As I expected, when I passed the alarm with this book, the alarm didn't respond except the sound of my heartbeat. When I came out with this book again, the alarm still stood beside me like a mute, turning a deaf ear to my behavior. I think I have discovered a new continent. Although it is a novel, the principle is similar. Iron bars are anti-theft in libraries or bookstores.

Satisfied, please adopt.