/**
 * struct Interval {
 *	int start;
 *	int end;
 *	Interval(int s, int e) : start(start), end(e) {}
 * };
 */
#include <vector>
class Solution {
public:
    /**
     * 代码中的类名、方法名、参数名已经指定,请勿修改,直接返回方法规定的值即可
     *
     * 
     * @param intervals Interval类vector 
     * @return Interval类vector
     */
    vector<Interval> merge(vector<Interval>& intervals) {
        // write code here
        int n=intervals.size();
        if(n==0 || n==1) return intervals;
        //将区间排序
        sort(intervals.begin(),intervals.end(),[](Interval a, Interval b){return a.start<b.start;});
        vector<Interval> res;
        res.push_back(intervals[0]);
        for(int i=1;i<n;i++){
            if(intervals[i].start <= res.back().end) 
            res.back().end = max(res.back().end, intervals[i].end);
            else
            res.push_back(intervals[i]);
        }
        return res;
    }
};