CodingHardcod-g930

Subject Grid dpLevel Senior–Staff~35 minCommon in Algorithms & data structures interviewsIndustries Software development

Question

Given an n x n integer matrix, a falling path picks one element from each row such that adjacent rows' chosen columns differ (you may not pick the same column in two consecutive rows). Return the minimum sum of such a falling path. The matrix is square with n between 1 and 200, values may be negative.

Implement

min_falling_path_two(grid: list[list[int]]) → int

Examples

in[[[1,2,3],[4,5,6],[7,8,9]]]out13

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.