is it possible to do quicksort of a list with only one passing?

Question

I am learning haskell and the function definition I see is:

quickSort (x : xs) = (quickSort less) ++ (x : equal) ++ (quickSort more)
                 where         


        

Answer 1

It does not seem to improve anything but:

qs (x:xs) = let (a,b) = partition (< x) xs in (qs a) ++ [x] ++ (qs b)