Given an integer array nums of unique elements, return all possible subsets (the power set). The solution set must not contain duplicate subsets.
1 <= nums.length <= 10, -10 <= nums[i] <= 10, All the numbers of nums are unique
Backtracking: at each index, choose to include or exclude the element. Alternatively, iterate and double subsets at each step.
def subsets(nums):
result = []
def backtrack(start, path):
result.append(path[:])
for i in range(start, len(nums)):
path.append(nums[i])
backtrack(i + 1, path)
path.pop()
backtrack(0, [])
return result