/** * 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; } * } */class Solution {    public List
     
       insert(List
      
        intervals, Interval newInterval) {        List
       
         result = new ArrayList<>();                int i = 0;        while (i < intervals.size() && intervals.get(i).end < newInterval.start) {            result.add(intervals.get(i++));        }                while (i < intervals.size() && intervals.get(i).start <= newInterval.end) {            newInterval = new Interval(Math.min(newInterval.start, intervals.get(i).start),                                       Math.max(newInterval.end, intervals.get(i).end));            i++;        }        result.add(newInterval);                while (i < intervals.size()) {            result.add(intervals.get(i++));        }        return result;    }}
       
      
     

 

Since the input is ordered and not overlapped intervals. It is OK to have this kind of simply implementation.