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

Lists & Arrays easy

Insert into a Sorted List

Implement a function that inserts a value into a sorted list at the correct position using binary search.

lists binary-search insertion

Data Structures & Algorithms easy

Binary search

Return the index of target in a sorted list, or -1 if not present.

searching binary-search

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 easy

Binary Search Tree Class

Build a BinarySearchTree class and a sequence runner that executes a list of operations.

binary-search-tree classes traversal

Trees & Binary Trees easy

Insert into BST

Implement insertion into a Binary Search Tree while maintaining BST properties.

binary-search-tree recursion tree

Binary Search easy

Lower Bound Binary Search

Implement binary search to find the first index where an element is not less than a given target.

binary-search search arrays

Binary Search easy

Upper Bound Binary Search

Write a function that returns the index of the first element greater than a target in a sorted list.

binary-search arrays searching

Binary Search easy

First Bad Version

Implement a function to find the first bad version in a sorted range using binary search.

binary-search search array

Showing 1–8 of 8 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.