You're learning the foundation of all backtracking. If you can't generate subsets, you won't solve Combination Sum, Permutations, or N-Queens. Google, Meta, and Amazon ask this regularly. Your interviewer tests whether you understand the backtracking template. The binary decision tree mental model applies to many problems: include/exclude each element, then combine results.
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$ curl repovive.com/roadmaps/maang-interview-prep/backtracking/subsets-why-this-problem
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