题解 | #牛群喂食#

class Solution {
public:
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 
     * @param candidates int整型vector 
     * @param target int整型 
     * @return int整型vector<vector<>>
     */
    vector<vector<int>> result;
    vector<int> path;
    void backTracking(vector<int>& candidates,int target,int sumNum)
    {
        if (sumNum == target)
        {
            result.push_back(path);
            return;
        }
        for (int i = 0;i < candidates.size();++i)
        {
            if (sumNum + candidates[i] > target)
            {
                continue;
            }
            path.push_back(candidates[i]);
            sumNum += candidates[i];
            backTracking(candidates,target,sumNum);
            sumNum -= candidates[i];
            path.pop_back();
        }
    }
    vector<vector<int> > cowCombinationSum(vector<int>& candidates, int target) 
    {
        // write code here
        backTracking(candidates, target,0);
        set<vector<int>> temp;
        for (auto it : result)
        {
            sort(it.begin(),it.end());
            temp.insert(it);
        }
        result.clear();
        for (auto it : temp)
        {
            result.push_back(it);
        }
        return result;
    }
};

不太会去重