No.218 - LeetCode[78] Subsets - 数组中所有子集

/*
 * @lc app=leetcode id=78 lang=cpp
 *
 * [78] Subsets
 */

// @lc code=start
class Solution {
public:
    vector<vector<int>> subsets(vector<int>& nums) {
        int N = nums.size();
        vector<vector<int>> ans;
        vector<int> path;
        dfs(ans,path,nums,0,N);
        return ans;
    }
    void dfs(vector<vector<int>>& ans,vector<int>& path,vector<int>& nums,int L,int N){
        ans.push_back(path);
        for(int i=L;i<N;i++){
            path.push_back(nums[i]);
            dfs(ans,path,nums,i+1,N);
            path.pop_back();
        }
    }
};
// @lc code=end