Practice Arena

Python Coding
Challenges

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925 challenges 556 easy 323 medium 46 hard

All Easy Medium Hard

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

Strings & Text easy

Snake case to camel case

Implement a function that converts snake_case strings to camelCase.

strings case-conversion text-processing

Strings & Text easy

Camel case to snake case

Write a function that converts camelCase input to snake_case while handling acronyms and numbers correctly.

strings case-conversion parsing

Strings & Text easy

Kebab Case a Phrase

Implement a function that converts a phrase into lowercase kebab-case, handling spaces, punctuation, and camelCase.

strings case-conversion regex

Strings & Text easy

Camel Case Converter

Write a function that converts a space-separated phrase into lower camelCase.

strings casing manipulation

Strings & Text easy

Kebab Case Converter

Implement a function that converts any string to kebab-case, handling spaces, underscores, camelCase, and punctuation.

strings case-conversion parsing

Strings & Text easy

Split on camelCase

Given a camelCase string, split it into words at uppercase letters and return them as lowercase words.

strings parsing camelcase

Data Structures & Algorithms easy

Lowest Common Ancestor in a Binary Search Tree

Implement a function to find the lowest common ancestor of two node values in a binary search tree.

Trees & Binary Trees medium

Lowest Common Ancestor in a Binary Tree

Implement a function to find the lowest common ancestor (LCA) of two nodes in a binary tree.

binary-tree dfs recursion

Showing 1–8 of 8 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.