Problem

leetcode链接problem

Code

好像有点对回溯有点味道了，上代码吧。

class Solution {
public: 
    vector<vector<int>> res;
    vector<int> row;
    vector<vector<int>> combinationSum2(vector<int>& candidates, int target) {
       
        if(candidates.empty())
            return res;
        sort(candidates.begin(),candidates.end());
        combination(candidates,target,0);
        return res;
    }
    void combination(vector<int>& candidates, int target, int index){
        if(target<0)
            return;
        if(target==0){
            res.push_back(row);
            return;
        }
        else{
            for(int i=index;i<candidates.size();++i){
                if (i > index && candidates[i] == candidates[i - 1])
                    continue;
                row.push_back(candidates[i]);
                combination(candidates,target-candidates[i],i+1);
                row.pop_back();
            }
        }
    }
};