Insert Interval and Merge Intervals

Given a set of non-overlapping intervals, insert a new interval into these intervals (first problem), then merge on the set of intervals after insertion (second problem). The interval endpoints are sorted, but there might exist overlapping intervals. Example 1: Input: intervals = [[1,3],[6,9]], newInterval = [2,5] Output: [[1,5],[6,9]] Example 2: Input: intervals = [[1,2],[3,5],[6,7],[8,10],[12,16]], newInterval = [4,8] Output: [[1,2],[3,10],[12,16]] Constraints intervals[i][0] <= intervals[i][1] newInterval is a valid interval and is already sorted. Write a function to complete the above functionality, accurately inserting and merging intervals. Example Input [[[1,3],[6,9]], [2,5]]