Leetcode 252 Meeting Rooms

Given an array of meeting time intervals consisting of start and end times [[s1,e1],[s2,e2],...] (si < ei), determine if a person could attend all meetings.

For example,
Given [[0, 30],[5, 10],[15, 20]],
return false.

Solution 1: Sort the interval, make sure there is no overlap.

 public class Solution {  
   class InterComp implements Comparator<Interval> {  
     @Override  
     public int compare(Interval a, Interval b) {  
       return a.start-b.start;  
     }  
   }  
   public boolean canAttendMeetings(Interval[] intervals) {  
     int n=intervals.length;  
     Arrays.sort(intervals,new InterComp());  
     for (int i=1; i<n; i++) {  
       if (intervals[i].start<intervals[i-1].end) return false;  
     }  
     return true;  
   }  
 }