[LeetCode] 56. Merge Intervals（vector sort）

/**
 * 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:
    static bool cmp(Interval &a,Interval &b)
    {
        return a.start < b.start;
    }
    vector<Interval> merge(vector<Interval>& intervals)
    {
        if(intervals.empty()) return vector<Interval> {};
        sort(intervals.begin(),intervals.end(),cmp);
        vector<Interval> res;
        res.push_back(intervals[0]);
        for(int i = 1; i < intervals.size(); i ++)
        {
            if(intervals[i].start > res.back().end)
                res.push_back(intervals[i]);
            else
                res.back().end = max(res.back().end, intervals[i].end);
        }
        return res;
    }
};