Solution: Interval List Intersections

Explore an efficient method to solve the interval list intersections problem by iterating through two sorted interval lists simultaneously. Learn how to compare interval endpoints systematically, identify overlaps, and return all intersecting intervals with O(n + m) time complexity, optimizing beyond the naive approach.

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Statement
Solution
- Naive approach
- Optimized approach using intervals

Statement

Given two lists of closed intervalsA closed interval [start, end] (with start <= end) includes all real numbers x such that start <= x <= end., intervalListA and intervalListB, return the intersection of the two interval lists.

Each interval in the lists has its own start and end time and is represented as [start, end]. Specifically:

intervalListA[i] = [start_i, end_i]
intervalListB[j] = [start_j, end_j]

The intersection of two closed intervals i and j is either:

An empty set, if they do not overlap, or
A closed interval [max(start_i, start_j), min(end_i, end_j)] if they do overlap.

Also, each list of intervals is pairwise disjoint and in sorted order.

Constraints:

$0 \leq$ ...