Practice Arena

Python Coding Challenges

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819 challenges 506 easy 280 medium 33 hard
Data Structures & Algorithms medium

Shortest Path in Binary Matrix

Implement BFS to find the shortest path length from (0,0) to (n-1,n-1) in an n x n binary matrix, moving through 0 cells in 8 directions.

bfs grid shortest-path
+30 pts 30m
Dynamic Programming medium

Maximal square

Given a 2D binary matrix of 0s and 1s, compute the area of the largest square containing only 1s.

dynamic-programming matrix maximal-square
+30 pts 30m
Dynamic Programming medium

Maximal square matrix

Given a 2D binary matrix of 0s and 1s, find the side length of the largest square containing only 1s.

dynamic-programming matrix maximum-square
+25 pts 30m
Dynamic Programming medium

Maximal rectangle in matrix

Given a matrix of 0s and 1s, compute the area of the largest rectangle consisting only of 1s.

dynamic programming binary matrix histogram
+25 pts 30m
Matrix & 2D Arrays medium

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.

matrix bfs distance
+25 pts 30m
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

Shortest Path in Binary Matrix

Compute the shortest path length from top-left to bottom-right in a binary matrix using 8-directional moves.

matrix bfs shortest-path
+30 pts 25m
Matrix & 2D Arrays medium

Count square submatrices with all ones

Count all square submatrices consisting entirely of 1s in a binary matrix.

matrix dynamic-programming counting
+25 pts 25m

Showing 8 challenges

Guide: free Python coding challenges

Practice Python by solving problems

PythonSkillset challenges are hands-on coding exercises from beginner to advanced. Open a challenge, read the problem, write Python in the split-pane editor, and run tests with Pyodide — no install required.

How to use the arena

  1. Pick a category — basics, algorithms, strings, and more
  2. Open a challenge, read the statement, and edit the starter code
  3. Run tests, fix failures, then try a related quiz or tutorial lesson

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.