Count Leading Zeros
Write a function that returns the number of leading zeros in a list of integers.
Cumulative Sum Vectorized
Implement a function that returns the cumulative sum of a list of numbers.
Running Maximum
Implement a function that returns a list where each element is the largest value seen so far.
Difference of Consecutive Elements
Given a list of numbers, return a new list where each element is the difference between consecutive elements.
Range-like generator
Implement a custom generator that yields numbers like Python's range but with flexible bounds.
Collatz Generator
Implement a generator function that yields the Collatz sequence starting from a given positive integer.
Digit Expansion Generator
Create a generator that lazily yields each decimal digit of a non-negative integer from most significant to least significant.
Zip Longest Fill
Create an iterator that yields lists from multiple iterables, padding with a fill value when lengths differ.
Lucas Sequence
Implement a function to compute the n-th Lucas number using iteration or recursion with memoization.
Subset XOR sum
Given a list of integers, compute the bitwise XOR of each non-empty subset and return the sum of those XOR totals.
Showing 1–10 of 10 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
- 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.