Matrix addition operator
Implement a Matrix class that supports + and * operators.
Complex Number Class
Implement a Complex class supporting addition, subtraction, multiplication, division, equality, and string formatting.
Class Method Factory
Create a class method factory that dynamically adds methods to a class based on a mapping of names to behaviors.
Reentrant Lock Manager
Implement a ReentrantLock class with acquire, release, locked, owner, and helper functions that test thread-safety with real threads.
Design Twitter Feed
Implement a Twitter class with postTweet, getNewsFeed, follow, and unfollow methods.
Seat Manager Design
Implement a SeatManager class that supports reserving the smallest available seat and unreserving seats.
Design Browser History
Implement a BrowserHistory class that supports visit, back, and forward navigation with step counts.
2D Vector dataclass
Implement a Vector2D dataclass with +, -, scalar *, dot product, and magnitude.
Metaclass Registry
Implement a metaclass that automatically registers every subclass in a class-level registry.
Descriptor Property
Create a descriptor class that ensures attribute values are positive integers.
Levenshtein Distance
Implement the classic Levenshtein distance algorithm to measure string similarity.
Edit Distance (Levenshtein Distance)
Implement the classic edit distance algorithm to find the minimum number of single-character edits required to transform one string into another.
0/1 Knapsack
Implement the classic 0/1 Knapsack dynamic programming solution to maximize value under a weight capacity.
Maximum Average Pass Ratio
Given class pass/total counts and extra students, maximize the average pass ratio by assigning extra students optimally.
Showing 1–14 of 14 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.