CodingEasycod-g871

Subject Stream processingLevel Entry–Mid~15 minCommon in Distributed systems · Algorithms & data structures interviewsIndustries Software development

Question

Given a stream of integers and a window size `k`, return the maximum sum of any contiguous window of exactly `k` elements. If `k` is not a positive integer or is larger than the stream length, return `-1`. The stream may contain negatives.

Implement

max_window_sum(stream: list[int], k: int) → int

Examples

in[[1,2,3,4,5],2]out9

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.