"""
78. Subsets
Difficulty: Medium
https://leetcode.com/problems/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]]

Example 2:

Input: nums = [0]
Output: [[],[0]]



Constraints:

        • 1 <= nums.length <= 10

        • -10 <= nums[i] <= 10

        • All the numbers of nums are unique.
"""


class Solution:
    def subsets(self, nums: list[int]) -> list[list[int]]:
        res = []

        def backtrack(i, path):
            res.append(path[:])
            for num_idx in range(i, len(nums)):
                path.append(nums[num_idx])
                backtrack(num_idx + 1, path)
                path.pop()

        backtrack(0, [])
        return res