Spiral Matrix Order
Given a 2D matrix, return all elements in clockwise spiral order starting from the top-left.
Valid Sudoku Board
Determine if a 9x9 Sudoku board is valid by checking rows, columns, and 3x3 sub-boxes.
Number of Islands
Given a 2D grid of '1' (land) and '0' (water), count the number of islands surrounded by water.
Max Area of Island
Given a 2D grid of 0s and 1s, find the maximum area of a connected group of 1s.
01 Matrix Nearest Zero
Given a binary matrix, return a matrix of the same shape where each cell contains the Manhattan distance to the nearest 0.
Rotting Oranges Time
Given a grid of fresh, rotten, and empty cells, compute the minimum minutes until all fresh oranges rot, or -1 if some are unreachable.
Showing 6 challenges · Matrix & 2D Arrays
Matrix & 2D Arrays — Python coding challenges
What you will find here
This page lists matrix & 2d arrays challenges — real Python problems you solve in the browser IDE with instant test feedback. Each challenge includes a clear brief, starter code, and automated checks.
Challenges vs tutorials and quizzes
Challenges test what you can build under constraints. For guided teaching, use our Python tutorials. For quick checks, try quizzes or copy snippets from code samples.