For each element, you have two choices: include it or exclude it. This forms a binary decision tree. At each level, branch into "take this element" and "skip this element." When you've decided for all elements, you have one complete subset. Here's the insight: use a start index to avoid duplicates. Only consider elements from the current index onward.
##### ###### ##### ### # # ### # # ###### ## ## ## ## ## ## ## # # # # # ## ##### #### ##### # # # # # # # #### ## # ## ## ## ## # # # # # ## ## # ###### ## ### # ### # ######
$ curl repovive.com/roadmaps/maang-interview-prep/backtracking/subsets-hint
░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░███████████████████████████████████████████████████████████████████████████