Leetcode #39. Combination Sum

Leetcode #39. Combination Sum

题目

https://leetcode.com/problems/combination-sum/description/

代码

class Solution {
public:
    void foo(vector<int>& candidates, int target, int cidx, vector<int> cursol, vector<vector<int>>& allsol) {
        if (target == 0) {
            allsol.push_back(cursol);
            return;
        }
        if (target < candidates[cidx]) return;

        for (int i = cidx; i < candidates.size(); i++) {
            if (target < candidates[i]) break;

            cursol.push_back(candidates[i]);
            foo(candidates, target - candidates[i], i, cursol, allsol);
            cursol.pop_back();
        }
    }
    vector<vector<int>> combinationSum(vector<int>& candidates, int target) {
        vector<int> csol;
        vector<vector<int>> allsol;
        sort(candidates.begin(), candidates.end());

        foo(candidates, target, 0, csol, allsol);
        return allsol;
    }
};