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Insert Interval

Detailed guide and Python implementation for the 'Insert Interval' problem.

Problem Statement

Easy

You are given an array of non-overlapping intervals intervals where intervals[i] = [starti, endi] represent the start and the end of the ith interval and intervals is sorted in ascending order by starti. You are also given an interval newInterval = [start, end] that represents the start and end of another interval. Insert newInterval into intervals such that intervals is still sorted in ascending order by starti and intervals still does not have any overlapping intervals (merge overlapping intervals if necessary).

Return intervals after the insertion.

Write a function insert(intervals: List[List[int]], newInterval: List[int]) -> List[List[int]].

Constraints
  • 0 <= len(intervals) <= 10^4
  • intervals[i].length == 2
  • 0 <= starti <= endi <= 10^5
  • intervals is sorted by starti in ascending order
  • newInterval.length == 2
  • 0 <= start <= end <= 10^5

Examples

Example 1
Input
intervals = [[1,3],[6,9]], newInterval = [2,5]
Output
[[1,5],[6,9]]
Explanation

The new interval [2,5] overlaps with [1,3], so they are merged into [1,5].

Example 2
Input
intervals = [[1,2],[3,5],[6,7],[8,10],[12,16]], newInterval = [4,8]
Output
[[1,2],[3,10],[12,16]]
Explanation

Because [4,8] overlaps with [3,5],[6,7],[8,10], they merge to [3,10].

Need a Hint?
Consider using Intervals-specific data structures like sets or heaps.
Edge Cases to Watch
  • Empty input structures
  • Single element inputs
  • Large numerical bounds

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