Ordinary male and female dormitories open at 6 am and close at midnight 12. If you want to go in and out during this period, you can register several times and meet with the supervisor. If you don't have a reasonable explanation, you will receive a warning letter, and if it is serious, you will ask to leave the dormitory ... In principle, visitors should leave before closing the door, except the dormitory, and you can enter and leave freely even in the morning. Postgraduate dormitories are completely exceptional, because there are married student dormitories.