Near the door. This is not a land of feng shui. There is generally a fan light switch at the entrance of the dormitory, which is responsible for turning on or off the lights or fans.
There is a bed in the back. The bathrooms in dormitories are generally arranged in the innermost part, so the beds here are also "battlegrounds for military strategists". Get up early at night to wash, wash clothes and have a rest. I don't think there is anything during class, but students sleeping here may be disturbed during weekends.
The middle bed. The middle bed is a better choice for the whole dormitory. Although there are people at both ends, either facing someone's head or feet, as long as you put on curtains, you can greatly protect your privacy.