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Subsets

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Given an integer array nums of unique elements, return all possible subsets (the power set).

The solution set must not contain duplicate subsets. Return the solution in any order.

Example 1:

Input: nums = [1,2,3]
Output: [[],[1],[2],[1,2],[3],[1,3],[2,3],[1,2,3]]
Explanation: The power set of [1,2,3] includes all 2^3 = 8 subsets.

Example 2:

Input: nums = [0]
Output: [[],[0]]
Explanation: The only element is 0, so we have the empty set and {0}.

Examples

Example 1

Input: nums = [1,2,3]

Output: [[],[1],[2],[1,2],[3],[1,3],[2,3],[1,2,3]]

Explanation: The power set of [1,2,3] includes all 8 subsets, from the empty set to the full array.

Example 2

Input: nums = [0]

Output: [[],[0]]

Explanation: With a single element, there are only two subsets: the empty set and the set containing 0.

Example 3

Input: nums = [1,2]

Output: [[],[1],[2],[1,2]]

Explanation: The power set of [1,2] has 4 subsets.

Constraints

  • -1 <= nums.length <= 10
  • --10 <= nums[i] <= 10
  • -All the numbers of nums are unique

Optimal Complexity

Time

O(n * 2^n)

Space

O(n * 2^n)

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