Code Room
CodingMediumcod-g003
Subject DfsLevel Mid–Senior~25 minCommon in Algorithms & data structures interviewsIndustries Software development

Question

Given an m x n grid of integers, a region is a maximal group of 4-directionally connected cells that all share the same value. Return the size (number of cells) of the largest region in the grid. The grid has at least one cell. Values can be any integers including negatives.

Implement
largest_region(grid: list[list[int]]) → int
Examples
in[[[1,1,2],[1,2,2],[3,3,2]]]out4
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.