Given a set of candidate numbers (C) and a target number (T), find all unique combinations in C where the candidate numbers sums to T.
The same repeated number may be chosen from C unlimited number of times.
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 2,3,6,7 and target 7,
A solution set is: [7] [2, 2, 3]
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#include <iostream>
#include <vector>
#include <algorithm>
using namespace std; class Solution {
public:
vector<vector<int > > ret;
vector<vector<int> > combinationSum(vector<int> &candidates, int target) {
vector<int > stk;
ret.clear();
vector<int > tmp(candidates.begin(),candidates.end());
sort(tmp.begin(),tmp.end());
helpFun(tmp,target,,stk);
return ret;
} void helpFun(vector<int> & cand,int tar, int idx,vector<int > & stk)
{
if(tar<) return ;
if(tar==){
ret.push_back(stk);
return ;
}
if(idx==cand.size()) return;
stk.push_back(cand[idx]);
helpFun(cand,tar-cand[idx],idx,stk);
stk.pop_back();
helpFun(cand,tar,idx+,stk);
}
}; int main()
{
vector<int > cand = {,,,};
Solution sol;
vector<vector<int > > ret=sol.combinationSum(cand,);
for(int i =;i<ret.size();i++){
for(int j=;j<ret[i].size();j++)
cout<<ret[i][j]<<" ";
cout<<endl;
}
return ;
}