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, … , a_k) must be in non-descending order. (ie, a₁ ≤ a₂ ≤ … ≤ a_k).
• 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] 

class Solution {public:    void comb(vector<int> &num, vector<int> &count, vector< vector<int> > &result,     vector<int> &record, int target, int sum, int pos, int s)    {        if (sum == target)        {            result.push_back(vector<int>());            for (int i = 0; i < pos; ++i)                result.back().push_back(record[i]);        }                if (pos >= record.size() || sum > target)            return;                for(int i = s; i < num.size(); ++i)          {             if (count[i] > 0)            {                count[i]--;                record[pos] = num[i];                comb(num, count, result, record, target, sum+num[i], pos+1, i);                 count[i]++;            }        }    }        vector<vector<int> > combinationSum2(vector<int> &num, int target) {        // Start typing your C/C++ solution below        // DO NOT write int main() function        int nSize = num.size();        vector< vector<int> > result;        if (nSize == 0) return result;        sort(num.begin(), num.end());        vector<int> nums;        nums.push_back(num[0]);        vector<int> count;        count.push_back(1);        for(int i = 1; i < num.size(); ++i)        {            if (num[i] == nums.back())                ++count.back();            else            {                nums.push_back(num[i]);                count.push_back(1);            }        }        vector<int> record(nSize);        comb(nums, count, result, record, target, 0, 0, 0);        return result;    }};