Given a set of candidate numbers (C) (without duplicates) 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.

The solution set must not contain duplicate combinations.

For example, given candidate set [2, 3, 6, 7] and target 7,

A solution set is:

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[

[7],

[2, 2, 3]

]

Solution

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classSolution {

private:

vector<int> tmp;

vector<vector<int> > res;

public:

vector<vector<int>> combinationSum(vector<int>& candidates, int target) {

sort(candidates.begin(), candidates.end());

dfs(candidates, target, 0);

return res;

}

voiddfs(vector<int>& candidates, int target, int index){