Approach Summary
Sort input. Backtrack with start index. Skip duplicates at the same level: if i > start && nums[i] == nums[i-1], continue.
How to Recognize This Pattern
- Subsets with duplicate numbers — avoid duplicate subsets
- Sort + skip duplicates at same recursion depth
Complexity Analysis
Time Complexity
O(n × 2ⁿ)
Space Complexity
O(n)
Tags
Array Backtracking Bit Manipulation