That sounds like your standard Morningside/Bruntsfield wedge the student in styles. You get some cracking examples of those - I think my favourite was a 5 bedroom flat with a floor space of 70-odd square metres. It was hilariously awful.
Standard approach seems to be to put a sofa in the kitchen, meaning the livingroom is now a bedroom. +1 room
Use the box room as a bedroom if possible. +1 room. Or make it in to a second shower room if not.
Split any room which has two windows (not unusual) in to two. Often add 1 or two rooms.
And lo, a 2 bedroom beautifully proportioned flat which would have had a big lounge, big kitchen and two decent doubles with a box room for storage is transformed in to a 5 or 6 bedroomed monstrosity!