Problem - Subsets

Given an integer array with distinct values, return all possible subsets (the power set). The solution set must not contain duplicate subsets.

For example, if nums $= [1, 2, 3]$, you return $[[], [1], [2], [3], [1,2], [1,3], [2,3], [1,2,3]]$. Notice the empty set is included.

This is simpler than the combinations problem because you do not have a fixed size. Every combination of any length is valid.