public:

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

vector<vector<int> > result;

vector<int> solution;

int sum = 0;

std::sort(num.begin(), num.end());

GetCombinations(num, sum, 0, target, solution, result);

return result;

}

void GetCombinations(vector<int>& candidates, int& sum, int level, int target,

vector<int>& solution, vector<vector<int> >& result) {

if (sum > target) return;

if (sum == target) {

result.push_back(solution);

return;

}

for (int i = level; i < candidates.size(); i++) {

sum += candidates[i];

solution.push_back(candidates[i]);

GetCombinations(candidates, sum, i + 1, target, solution, result);

solution.pop_back();

sum -= candidates[i];

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

i++;

}

}

/* code */

return 0;

}