78. Subsets

Given a set of distinct integers, nums, return all possible subsets (the power set).

Note: The solution set must not contain duplicate subsets.

Example:

Input: nums = [1,2,3]
Output:
[
  [3],
  [1],
  [2],
  [1,2,3],
  [1,3],
  [2,3],
  [1,2],
  []
]

class Solution {
public:
    vector<vector<int>> subsets(vector<int>& nums) {
        vector<vector<int> > result;
        vector<int> path;
        sort(nums.begin(), nums.end());
        result.push_back(path);
        dfs(nums, 0, path, result);
        return result;
    }
    
    void dfs(vector<int> &nums, int pos, vector<int> &path, vector<vector<int> > &result)
    {
        if(pos==nums.size())
            return;
        for(int i=pos; i<nums.size(); i++)
        {
            path.push_back(nums[i]);
            result.push_back(path);
            dfs(nums,i+1, path, result);
            path.pop_back();
        }
    }
};