LCR 079. 子集

主要应该考虑遍历的顺序

class Solution {
public:
    vector<vector<int>> subsets(vector<int>& nums) {

        vector<vector<int>> ans;
        vector<int> temp;
        dfs(nums,0,temp,ans);

        return ans;
    }

    void dfs(vector<int> &nums,int cur,vector<int> &temp,vector<vector<int>> &ans){


        ans.push_back(temp);
        if(cur >= nums.size()){
            return;
        }
        for(int i=cur;i<nums.size();++i){
            temp.push_back(nums[i]);
            dfs(nums,i+1,temp,ans);
            temp.pop_back();
        }
    }

};