find if two arrays contain the same set of integers without extra space and faster than NlogN

Question

I came across this post, which reports the following interview question:

Given two arrays of numbers, find if each of the two arrays have the same s

Answer 1

All I know is that comparison based sorting cannot possibly be faster than O(NlogN), so we can eliminate most of the "common" comparison based sorts. I was thinking of doing a bucket sort. Perhaps if this qn was asked in an interview, the best response would first be to clarify what sort of data those integers represent. For e.g., if they represent a persons age, then we know that the range of values of int is limited, and can use bucket sort at O(n). However, this will not be in place....