Non-overlapping Intervals

class Solution {
    public int eraseOverlapIntervals(int[][] intervals) {
        if(intervals.length == 0) return 0;
        int count = 0;
        Arrays.sort(intervals, new Comparator<int[]>(){
            public int compare(int[] a, int[] b){
                if(a[1] == b[1]){
                    return -(a[0] - b[0]);
                }
                return a[1] - b[1];
            }
        });
        int end = intervals[0][1];
        for(int i = 1; i<intervals.length; i++){
            if(intervals[i][0] < end){
                count++;
            }
            else{
                end = intervals[i][1];
            }
        }
        return count;
    }
}