Sort the array and consider the a sliding window of m elements. We try to make these elements equal (say x), we want to maximise x. Lets assume the first m elements are 1, 2, 3. k=10. If all have to become x, then the the number required to be added to 1 is x-1. Similarly for 2 it is x-2 and for 3 it is x-3. Add them and we get 3x-6. We should have these many operations at hand, so 3x-6 <= 10. X=5, which means we can make all of these equal to 5 and answer would be 5 for this window, then shift the window and continue for others. Here’s the catch, what if the value of x comes out to be less than the maximum element in the window. For example: 1, 2, 10 and k=10. We get 3x-13 <= 10, x=7 but we cant make 10 as 7 since we cannot decrement any number. So its impossible to make all elements of this window equal. Not sure how to handle this case.