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Python Coding
Challenges

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467 challenges 330 easy 120 medium 17 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

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 hard

Median of Two Sorted Arrays

Given two sorted arrays, return the median of the combined sorted array in O(log(min(n,m))) time.

median binary search arrays

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 medium

Delete Node in BST

Implement a function that deletes a key from a binary search tree and returns the new root.

binary-search-tree tree-traversal recursion

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 medium

Search in Rotated Array

Implement an efficient search in a rotated sorted array using modified binary search.

binary-search arrays search

Showing 7 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.