I'm a newb, but what i'd do is that when you see her , you use something like:
"Hey, U've been living same floor as I do, and we havn't talked at ALL, so I was like: lets introduce me (with smile on ur face and laidback body language)"
she will go blahblahblah and u introduce urself, say u got little time, get small conversation going (what does she study, why does she study would be good topics, since you are in dorm)
Be sure not to do it interview style, tell some small stories to her related to ur study, fir exanoke: I study laws, but it's really really boring, all teachers do is saying the same shit over and over, I gotta read 500 pages a week, barely got spare time. But hey, I wanna be lawyer so I gotta do what it takes right?
--> This shows DHV I think, as ur set on a goal and u do whatever it takes to get there
Then I would just say: "Well, gotta go. I'll cya around!" if it was only about studies for example
If she talks about hobbies: Going out with friends, sitting on terras drinking a wine
somewhere in the middle of conversation, say something like: U sound like a fun person to be with

Maybe we should get to know eachother a little bit better and go to a terras and have a drink later? then #close, keep conversation running for 1 more minute and get out.
Not too sure about the last one. I would keep it short, only introducing her and u, and get out. Next time u see her #close and chill together to build comfort and u know what
Hope it works, I'm new to this, so might not be usefull at all and even turn her off.