Python coding challenges: "modular-arithmetic"

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Math & Number Theory medium

Zeller Congruence Weekday

Implement a function that returns the weekday name for a given date using Zeller's congruence.

math modular-arithmetic date

+20 pts 20m

Math & Number Theory medium

Multinomial coefficient

Write a function to compute the multinomial coefficient efficiently for given nonnegative counts.

combinatorics math division

+20 pts 20m

Showing 2 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.

Python Coding Challenges