LeetCode OJ:Merge Intervals

Merge Intervals 

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].

/** * 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:    struct cmp{          bool operator()(const Interval& x, const Interval& y) const        {              if(x.start != y.start) return x.start < y.start;              else return x.end < y.end;          }      };    vector<Interval> merge(vector<Interval> &intervals) {        vector<Interval> result;        if(intervals.empty())return result;                sort(intervals.begin(), intervals.end(),cmp());          Interval cur = intervals[0];          for(int i=1;i<intervals.size();i++)          {              if(cur.end < intervals[i].start)              {                  result.push_back(cur);                  cur = intervals[i];              }else{                  cur.end = max(cur.end,intervals[i].end);              }          }          result.push_back(cur);         return result;    }};