Leetcode 40 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]]

与39类似，只是注意数字不能重复使用

http://blog.csdn.net/accepthjp/article/details/52452525

因而开始不用去重，搜索的过程中要注意避免重复搜索相同分支的情况

class Solution {public:    void dfs(vector<int> candidates,int target,vector<vector<int>>& result,vector<int> path)      {          if(target==0)          {              result.push_back(path);                  return ;          }         int t;        for(int i=candidates.size()-1;i>=0;i--)          {              if(candidates[i]==t)             {                candidates.pop_back();                continue;            }            t=candidates[i];            candidates.pop_back();            if(t>target) continue;              path.push_back(t);              dfs(candidates,target-t,result,path);              path.pop_back();          }      }      vector<vector<int>> combinationSum2(vector<int>& candidates, int target)       {          vector<vector<int>> result;          vector<int> path;          sort(candidates.begin(),candidates.end());          dfs(candidates,target,result,path);          return result;      } };