Question
A growth experiment dashboard shows each variant's conversion rate in basis points (hundredths of a percent) to avoid float noise. Given equal-length lists conversions and visitors, where variant i had conversions[i] sign-ups from visitors[i] visitors, return a list where entry i is floor(10000 * conversions[i] / visitors[i]). If a variant has zero visitors, use -1 for that entry. Example: conversions = [30, 45], visitors = [1000, 1200] gives [300, 375].
conversion_bps(conversions: list[int], visitors: list[int]) → list[int][[30,45],[1000,1200]]out[300,375]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.
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.