Running Total Window
Implement a function that returns a list of running totals, resetting to zero after each positive sum.
Rolling Window Mean
Given a list of numbers and a window size k, return a list of the means of every contiguous subarray of length k.
Consecutive available seats
Given a list of seat statuses, return the length of the longest consecutive run of available (0) seats.
Window Iterator
Implement a generator that yields consecutive windows of a given size from any iterable.
Best Time to Buy and Sell Stock
Given a list of daily stock prices, determine the maximum profit achievable by buying on one day and selling on a later day.
Longest Substring Without Repeating Characters
Implement a function that returns the length of the longest substring without repeating characters.
Showing 1–6 of 6 challenges · easy
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.