CodingEasycod-g1458

Subject IntervalsLevel Entry–Mid~10 minCommon in Algorithms & data structures interviewsIndustries Software development

Question

Given a list of closed integer intervals [start, end], count how many unordered pairs (i, j) with i < j overlap — that is, share at least one point. The list holds at most a few hundred intervals, so comparing every pair is acceptable. Example: [[1,3],[2,5],[6,8]] gives 1, because only the first two share points.

Implement

count_overlapping_pairs(intervals: list[list[int]]) → int

Examples

in[[[1,3],[2,5],[6,8]]]out1

What a strong answer looks like

State your approach and its time/space complexity out loud before you optimize. Handle the edge cases (empty input, duplicates, overflow), and say why you chose this over the brute force. Green tests are the floor, not the grade.

Learn the concepts

Vibe coding: describe the solution in plain language (or narrate it) and the coach grades your approach. Generating runnable code from your description is coming next.

Run or narrate your approach, then ask the coach.