How do you solve Subsets / Permutations with backtracking?

Question

Accepted Answer

Short answer: Subsets: at each index choose include/exclude (or loop-based cascading). Permutations: swap/choose unused elements recursively. Always discuss time complexity exponential in n and when to prune. Complexity Subsets O(n * 2^n); Permutations O(n * n!). Draw the decision tree for n=3 — it proves you understand recursion depth.