leetcode

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.
• 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:    vector<vector<int>> combinationSum2(vector<int>& candidates, int target) {        vector<int> out;        vector<vector<int> > res;        sort(candidates.begin(),candidates.end());        combinationSum2DFS(candidates,target,out,0,res);        return res;    }    void combinationSum2DFS(vector<int>& candidates,int target,vector<int>& out,int start,vector<vector<int> >&res)    {        if(target<0) return;        else if(target == 0) res.push_back(out);        else        {            for(int i=start;i<candidates.size();i++)            {                if(i>start && candidates[i]==candidates[i-1]) continue;                out.push_back(candidates[i]);                combinationSum2DFS(candidates,target-candidates[i],out,i+1,res);                out.pop_back();            }        }    }};