Typical quant stuff, not much advanced math, rather its like several math puzzle, I belive most of them were covered in the green book or red book(/Mark Josh's) You would be asked programming questions, which is for sure, but the depth may vary, depends on how much you claim you know on your resume and the background of the interviewer. It is more like how you present yourself to shine among those competitors, rather than giving a 'correct' answer only.