combination sum ii

Given a collection of candidate numbers (C) and a target number (T), find all unique combinations in C where the candidate numbers sums to T.

Each number in C may only be used once in the combination.

Note:
All numbers (including target) will be positive integers.
Elements in a combination (a1, a2, … , ak) must be in non-descending order. (ie, a1 ≤ a2 ≤ … ≤ ak).
The solution set must not contain duplicate combinations.
For example, given candidate set 10,1,2,7,6,1,5 and target 8,
A solution set is:
[1, 7]
[1, 2, 5]
[2, 6]
[1, 1, 6]

vector<vector<int> > combinationSum2(vector<int> &num, int target) {
vector<vector<int> >res;
vector<int>temp;
vector<bool>vis(num.size(),false);
sort(num.begin(),num.end());
dfs(num,target,0,temp,res,vis);
return res;
}
void dfs(vector<int>& num, int gap, int idx, vector<int>& temp, vector<vector<int> >& res, vector<bool>& vis){
if(gap == 0){
res.push_back(temp);
return;
}
for(int i=idx; i<num.size(); i++){
if(i > 0 && num[i] == num[i-1] && !vis[i-1]) continue;
if(num[i] > gap) return;
temp.push_back(num[i]);
vis[i] = true;
dfs(num,gap-num[i],i+1,temp,res,vis);
temp.pop_back();
vis[i] = false;
}
}