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Python Coding Challenges

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819 challenges 506 easy 280 medium 33 hard
Matrix & 2D Arrays medium

Spiral Matrix Order

Given a 2D matrix, return all elements in clockwise spiral order starting from the top-left.

matrix spiral traversal
+25 pts 25m
Matrix & 2D Arrays medium

Number of Islands

Given a 2D grid of '1' (land) and '0' (water), count the number of islands surrounded by water.

matrix graph bfs
+25 pts 30m
Matrix & 2D Arrays medium

Max Area of Island

Given a 2D grid of 0s and 1s, find the maximum area of a connected group of 1s.

grid dfs connected-components
+20 pts 25m
Matrix & 2D Arrays medium

Spiral Matrix Traversal

Implement a function that returns the elements of a 2D matrix in clockwise spiral order.

matrix traversal simulation
+20 pts 25m
Matrix & 2D Arrays medium

Search a 2D Matrix II

Implement an efficient search for a target in a matrix where each row and each column is sorted in ascending order.

matrix binary-search search
+20 pts 20m
Matrix & 2D Arrays medium

Number of Islands in a Matrix

Count the number of distinct islands (connected groups of 1s) in a 2D binary matrix.

matrix dfs bfs
+20 pts 20m
Matrix & 2D Arrays medium

Shift 2D Grid

Implement a function to shift a 2D grid right by k positions, flattening the grid and wrapping elements.

grid list modulo
+20 pts 20m
Matrix & 2D Arrays medium

Matrix Block Sum

Given a 2D matrix and a block size, compute the sum of each block centered at every cell.

matrix prefix-sum 2d-array
+25 pts 25m
Matrix & 2D Arrays medium

Word Search Matrix

Given a 2D board and a word, determine if the word can be formed by sequentially adjacent cells (horizontally or vertically), without reusing cells.

matrix dfs strings
+25 pts 30m

Showing 9 challenges · medium · 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.