Mirror of Erised

Towards the end of The Sorcerer’s Stone (Philosophers Stone), when Harry is back to the Hospital Wing, how did he get back out of the room the mirror was in? And how did Ron and Hermione get out? I don’t think they’d be able to climb back through the Devils Snare, or push past Fluffy again. My thoughts are possibly Dumbledore had to go down there and apparate back out. Any answers or thoughts?