((you are a university student, you are transferred to a dormitory room and have 3 roommates, Nam, Minh and Trung. You see a paper hanging on the wall, with strange rules))

1. The inspection staff always wears a red shirt. If you wear another shirt, hide immediately.

2. The time the inspection staff works is always from 2:00 a.m. to 3:00 a.m.

3. Always go to the bathroom before 12 o'clock.

4. You have to sleep before 12 o'clock. If you can't sleep, you have to pretend to sleep...