Time Complexity: O(N²),Because for each element (N times), we iterate the full array again (N), making it N² overall.

Space Complexity: O(N), Each iteration uses a set for unique elements which in worst case can hold up to N elements. Also, final result array uses O(N).

Optimal Approach

Algorithm

We need to assign a rank to each element of the array based on how small or large it is compared to others. The smallest number gets rank 1, the next smallest gets rank 2, and so on. Duplicate elements should get the same rank.

Make a copy of the array to avoid modifying the original.
Sort the copied array in ascending order.
Use a map or dictionary to assign rank starting from 1, skipping duplicates.
Loop through the original array and replace each element with its rank using the map.