Given a set of distinct integers, nums, return all possible subsets.
Note: The solution set must not contain duplicate subsets.
For example,
If nums = [1,2,3]
, a solution
is:
[ [3], [1], [2], [1,2,3], [1,3], [2,3], [1,2], [] ]
public class Solution {
public List<List<Integer>> subsets(int[] nums) {
Arrays.sort(nums);
List<List<Integer>> res = new ArrayList<>();
backtrack(res, new ArrayList<Integer>(), nums, 0);
return res;
}
private void backtrack(List<List<Integer>> res, List<Integer> temp_list, int[] nums, int pos) {
res.add(new ArrayList<>(temp_list));
for (int i = pos; i < nums.length; i++) {
temp_list.add(nums[i]);
backtrack(res, temp_list, nums, i + 1);
temp_list.remove(temp_list.size() - 1);
}
}
}