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

Lists & Arrays hard

Sliding window maximum

Return the maximum of each window of size k as it slides across an array.

sliding-window deque arrays

Data Structures & Algorithms hard

Largest Rectangle in Histogram

Given an array of bar heights, compute the largest rectangle that can be formed by consecutive bars.

histogram stack maximum-area

Dynamic Programming hard

Create Maximum Number

Given two arrays of digits and an integer k, merge them to form the largest number of length k.

arrays greedy dynamic-programming

Dynamic Programming hard

Cherry Pickup Maximum

Given a grid with cherries, find the maximum cherries you can collect using two paths from top-left to bottom-right.

dynamic-programming 2d-grid grid-walk

Numpy & Vectorized Computing hard

Index of maximum value

Return index of largest value (first on tie).

vectors arrays numpy-style

Showing 1–5 of 5 challenges · hard

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.