Code Room
CodingMediumcod-g093
Subject PartitioningLevel Mid–Senior~25 minCommon in Distributed systems interviewsIndustries Software development

Question

Given an integer array a, rearrange it so that elements alternate starting with a non-negative element: non-negative, negative, non-negative, negative, ... The relative order among the non-negatives and among the negatives must be preserved. If one group runs out, append the remaining elements of the other group in order. Treat 0 as non-negative.

Implement
rearrange_alternate(a: list[int]) → list[int]
Examples
in[[1,2,3,-4,-1,4]]out[1,-4,2,-1,3,4]
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.

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.