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819 challenges 506 easy 280 medium 33 hard

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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

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

Math & Number Theory easy

Modular Inverse

Implement a function that returns the modular inverse of a modulo m, or -1 if it does not exist.

modular-arithmetic euclid math

Math & Number Theory medium

Multinomial coefficient

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

combinatorics math division

Showing 3 challenges · Math & Number Theory

Math & Number Theory — Python coding challenges

What you will find here

This page lists math & number theory challenges — real Python problems you solve in the browser IDE with instant test feedback. Each challenge includes a clear brief, starter code, and automated checks.

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.