Practice Arena

Python Coding
Challenges

Write real Python in the browser. Instant feedback. From beginner to expert.

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

Heaps & Priority Queues medium

Task Scheduler Heap

Given a list of tasks and a cooldown, find the minimum number of CPU intervals needed to schedule all tasks without violating the cooldown.

heap queue greedy

Heaps & Priority Queues medium

Meeting Rooms II with Heaps

Given a list of meeting intervals, compute the minimum number of rooms required using a heap-based approach.

heap intervals greedy

Heaps & Priority Queues medium

Minimum Cost to Connect Sticks

Compute the minimum total cost to connect all sticks into one stick by repeatedly combining two sticks with the smallest lengths.

heap priority queue greedy

Matrix & 2D Arrays medium

Rotting Oranges Time

Given a grid of fresh, rotten, and empty cells, compute the minimum minutes until all fresh oranges rot, or -1 if some are unreachable.

bfs grid simulation

Numpy & Vectorized Computing easy

Minimum element in vector

Return smallest value or None when empty.

vectors arrays numpy-style

Showing 49–53 of 53 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.