class Solution {

public:

vector<vector<int>> combinationSum2(vector<int>& candidates, int target) {

vector<vector<int>> res;

vector<int> cur;

sort(candidates.begin(), candidates.end());

FindCombinationSum(candidates, target, 0, cur, res);

return res;

}

void FindCombinationSum(vector<int> candidates, int target, int start, vector<int> cur, vector<vector<int>>& res)

{

if (target == 0)

{

res.push_back(cur);

}

else if (target < 0 || start >= candidates.size())

{

return;

}

int i = start;

while (i < candidates.size())

{

if (target - candidates[i] < 0)

break;

cur.push_back(candidates[i]);

FindCombinationSum(candidates, target - candidates[i], i + 1, cur, res);

cur.pop_back();

while (i < candidates.size() - 1 && candidates[i] == candidates[i + 1]) i++;

//if (i > 0 && cnadidates[i] == candidates[i - 1]) i++;

i++;

}

}

};