【LeetCode】56. 合并区间

class Solution {
public:
    vector<vector<int>> merge(vector<vector<int>>& intervals) {
        if(intervals.empty())return {};
        sort(intervals.begin(),intervals.end());
        vector<vector<int>> res;
        res.push_back(intervals[0]);
        for(int i=1; i<intervals.size();++i){
            if(res.back()[1] >= intervals[i][0]) res.back()[1]=max(res.back()[1],intervals[i][1]);
            else res.push_back(intervals[i]);
        }return res;
    }
};