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, … , ak) must be in non-descending order. (ie, a1 ≤ a2 ≤ … ≤ ak).
- 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) {
sort(candidates.begin(), candidates.end());
backTracking(candidates,,target);
return result;
}
void backTracking(vector<int>& candidates, int depth, int target){
if(target==){
result.push_back(item);
return;
}
if(target< || depth >= candidates.size()) return;
item.push_back(candidates[depth] );
backTracking(candidates,depth+, target-candidates[depth]);
item.pop_back();
while(++depth<candidates.size() && candidates[depth]==candidates[depth-]);//avoid repetition
backTracking(candidates,depth, target);
}
private:
vector<int> item;
vector<vector<int>> result;
};