CodingMediumcod-g417

Subject MatrixLevel Mid–Senior~25 minCommon in Algorithms & data structures interviewsIndustries Software development

Question

Given an m x n integer matrix and an integer target, count the number of (non-empty) axis-aligned submatrices whose elements sum exactly to target. A submatrix is defined by a contiguous range of rows and a contiguous range of columns. Matrix dimensions are up to 100 x 100 and entries may be negative.

Implement

count_target_submatrices(matrix: list[list[int]], target: int) → int

Examples

in[[[0,1,0],[1,1,1],[0,1,0]],0]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.

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.