Thinking process

sort the array by starting times

Mistakes

don't need to consider the range, since if it's overlapped with the previous interval, then returns false

/**
 * Definition for an interval.
 * public class Interval {
 *     int start;
 *     int end;
 *     Interval() { start = 0; end = 0; }
 *     Interval(int s, int e) { start = s; end = e; }
 * }
 */

public class Solution {
    public boolean canAttendMeetings(Interval[] intervals) {
        Arrays.sort(intervals, new Comparator<Interval>(){
            public int compare(Interval a, Interval b) {
                return a.start - b.start;
            }
        });

        for (int i = 1; i < intervals.length; ++i) {
            if (intervals[i - 1].end > intervals[i].start) {
                return false;
            }
        }

        return true;
    }
}