78. Subsets

Subsets

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], [] ]

Solution

public class Solution {
    public List<List<Integer>> subsets(int[] nums) {
                Arrays.sort(nums);


        List<List<Integer>> result = new ArrayList<>();
        result.add(new ArrayList<>());
        subSets(nums, 0, result);
        return result;
    }

    public void subSets(int[] nums, int start, List<List<Integer>> result) {
        if (start >= nums.length) {
            return;
        }

        List<List<Integer>> temp = new ArrayList<>();
        result.forEach(item -> {
            List<Integer> cur = new ArrayList<Integer>(item);
            cur.add(nums[start]);
            temp.add(cur);
        });

        result.addAll(temp);

        subSets(nums, start + 1, result);
    }
}