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/**
 * 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; }
 * }
 */
 import java.util.*;
 
public class Solution {
    public Interval[] merge(Interval[] arr) {
        Arrays.sort(arr, new Comparator<Interval>(){
            public int compare(Interval one, Interval two){
                return one.start - two.start; //defualt behaviour
            }
            });
            
        int l = arr[0].start, r = arr[0].end;
        ArrayList<Interval> ans = new ArrayList<>();
        
        for(int i = 1; i < arr.length; i++){
            if(arr[i].start <= r){
                r = Math.max(r, arr[i].end);
            }else{
                ans.add(new Interval(l, r));
                l = arr[i].start;
                r = arr[i].end;
            }
        }
        ans.add(new Interval(l, r));
        
        Interval[] a = new Interval[ans.size()];
        for(int i = 0 ; i < a.length; i++){
            a[i] = ans.get(i);
        }
        return a;
    }
}