Nowadays, staying up late has become the norm for young people, and college students are no exception. I usually go to bed at 12 o'clock at night when I study, then get up at about 7: 30 in the morning, and then brush my teeth and wash my face to go to class. So in my opinion, it is enough for college students to sleep for about seven and a half hours. You live in a dormitory. Many times, your roommate may not sleep before twelve o'clock, or someone will play games after twelve o'clock. It is unlikely to rest before twelve o'clock, but it is usually quiet after twelve o'clock. When you sleep when there is no noise, your sleep quality will be higher. This is also my personal experience. In a word, in my opinion, it is best not to spend less than seven hours, otherwise the brain will not have a rest and there will be no energy to study the next day.