Implement it on LeetCode. Alternative: swap-based approach. Swap element at index i with elements from i to n-, recurse with i+, then swap back. Follow-up: Permutations II has duplicates. Sort first and skip duplicates at the same level (if nums[i] == nums[i-] and !visited[i-], skip).
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$ curl repovive.com/roadmaps/maang-interview-prep/backtracking/permutations-implementation
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