Norwich is different and I never lived there only visited, but if memory serves, there are no actual rooms on the ground floor. Because of the slope the ground floor only exists at the front and the middle floor rooms at the back are actually at ground level. So I think 1-48 middle and 49-96 top (12 per corridor) with some weird ones with letters in F2 or 23A scattered around just to confuse.
As for international etc, that sort of thing changes between years and no-one knows who decides.