[Leetcode] #56 Merge Intervals

Discription
Given a collection of intervals, merge all overlapping intervals.For example,
Given 

[1,3],[2,6],[8,10],[15,18]

,
return 

[1,6],[8,10],[15,18]

.
Solution/**
* Definition for an interval.
* struct Interval {
* int start;
* int end;
* Interval() : start(0), end(0) {}
* Interval(int s, int e) : start(s), end(e) {}
* };
*/
class Solution {
public:
vector<Interval> merge(vector<Interval>& intervals) {
vector<Interval> res;
if (intervals.empty()) return res;
sort(intervals.begin(), intervals.end(), [](Interval a, Interval b) {return a.start<b.start; });
res.push_back(intervals[0]);
for (int i = 1; i<intervals.size(); i++) {
if (res.back().end<intervals[i].start) res.push_back(intervals[i]);
else res.back().end = max(res.back().end, intervals[i].end);
}
return res;
}
};GitHub-Leetcode:https://github.com/wenwu313/LeetCode