Code Room
CodingMediumcod-g851
Subject MatrixLevel Mid–Senior~25 minCommon in Algorithms & data structures interviewsIndustries Software development

Question

A brick wall is a list of rows; each row is a list of positive brick widths, and all rows sum to the same total width. You want to draw a single vertical line from top to bottom that crosses the FEWEST bricks (a line along a brick's edge does not cross it). The line cannot be drawn along the wall's far-left or far-right edge. Return the minimum number of bricks crossed.

Implement
least_bricks(wall: list[list[int]]) → int
Examples
in[[[1,2,2,1],[3,1,2],[1,3,2],[2,4],[3,1,2],[1,3,1,1]]]out2
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.