Practice Arena

Python Coding
Challenges

Write real Python in the browser. Instant feedback. From beginner to expert.

925 challenges 556 easy 323 medium 46 hard

All Easy Medium Hard

All Python Basics Strings & Text Lists & Arrays Dicts & Sets Functions & Closures OOP & Classes Data Structures & Algorithms Advanced Python Iterators & Generators Decorators & Context Managers Error Handling & Exceptions Regular Expressions Math & Number Theory Bit Manipulation Dynamic Programming Trees & Binary Trees Graphs & Graph Algorithms Recursion & Backtracking Greedy Algorithms Binary Search Two Pointers & Sliding Window Stacks & Queues Heaps & Priority Queues Linked Lists Matrix & 2D Arrays Datetime & Time Calculations Data Formats & Parsing SQL & SQLite Numpy & Vectorized Computing Cryptography & Hashing

Linked Lists medium

Remove duplicate values

Keep first occurrence of each value while preserving order.

linked-list lists pointers

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

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

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

Matrix & 2D Arrays medium

Regions Cut by Slashes

Given a grid of slashes, count the number of connected regions formed by the slashes and the grid borders.

grid dfs union-find

Numpy & Vectorized Computing medium

Reverse vector order

Return elements in opposite order.

vectors arrays numpy-style

Showing 25–30 of 30 challenges · medium

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

Pick a category — basics, algorithms, strings, and more
Open a challenge, read the statement, and edit the starter code
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.