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 10,1,2,7,6,5 and target 8, 
A solution set is: 
[1,7] 
[2,6] 
#include<iostream> #include<vector> #include<algorithm> #include<numeric> #include<set> using namespace std; void FindcombinationSum(vector<vector<int> >&ResultVector,vector<int> &candidates,vector<int> &Oneresult,int target,int num = 0) { if (accumulate(Oneresult.begin(),Oneresult.end(),0) >= target) return; for (int i = num; i != candidates.size();++i) { if (candidates[i] == candidates[i - 1] && i>num)//保证不前1个重复数字必须被使用 continue; Oneresult.push_back(candidates[i]); int sum = accumulate(Oneresult.begin(),0); if (sum == target) ResultVector.push_back(Oneresult); FindcombinationSum(ResultVector,candidates,Oneresult,target,i + 1); Oneresult.pop_back(); } } vector<vector<int> > combinationSum(vector<int> &candidates,int target) { vector<vector<int> > ResultVector; vector<int> Oneresult; sort(candidates.begin(),candidates.end()); FindcombinationSum(ResultVector,target); return ResultVector; }