Combination Sum

class Solution {
    private:
        vector<vector<int>> res;
        const int index_count=10000;
        
public:
    void findSet(int sum,vector<int>& candidates,int target,int index[],int n )
    {
        if(sum>target)
        return;
        if(sum==target)
        {
            vector<int> result;
            for(int i=1;i<=n;i++)
            {
                result.push_back(candidates[index[i]]);
            }
            res.push_back(result);
            return;
        }
        for(int j=index[n];j<candidates.size()&&(target>=candidates[j]);j++)
        {
            index[n+1]=j;
            findSet(sum+candidates[j],candidates,target,index,n+1);
        }
    }
    vector<vector<int>> combinationSum(vector<int>& candidates, int target) {
        sort(candidates.begin(),candidates.end());
        int *index=new int [index_count];
         memset(index,0,sizeof(int)*index_count);
        res.clear();
        findSet(0,candidates,target,index,0);delete[] index;
        return res;
    }
};