/**
 * Definition of Interval:
 * public class Interval {
 *     public int start, end;
 *     public Interval(int start, int end) {
 *         this.start = start;
 *         this.end = end;
 *     }
 * }
 */

class Solution {
    public boolean canAttendMeetings(List<Interval> intervals) {
        Collections.sort(intervals, (a, b) -> Integer.compare(a.start, b.start));
        int n = intervals.size();
        for(int i=1; i<n; i++) {
            // check if current overlaps with previous one
            Interval cur = intervals.get(i);
            Interval prev = intervals.get(i-1);
            if(cur.start < prev.end) {
                return false;
            }
        }
        return true;
    }
}