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

Greedy Algorithms medium

Jump Game Reachable

Given an array of non-negative integers where each element is the maximum jump length, determine if you can reach the last index.

greedy arrays jump-game

Binary Search easy

Find Indices of Target in Sorted List

Given a sorted list and a target, return the indices of its first and last occurrence, or [-1, -1] if absent.

binary-search sorted range

Binary Search medium

Search 2D Matrix

Given a sorted 2D matrix with sorted rows and first element of each row greater than last of previous, find target efficiently.

binary search 2d matrix searching

Two Pointers & Sliding Window medium

Minimum Size Subarray Sum

Given an array of positive integers, return the minimal length of a contiguous subarray with sum at least target, or 0 if none exists.

sliding-window two-pointers array

Stacks & Queues medium

Asteroid Collision

Simulate asteroid collisions with a stack and return the remaining asteroids in original order.

stack simulation arrays

Heaps & Priority Queues easy

Last Stone Weight

Given an array of stone weights, repeatedly smash the two heaviest stones and return the last remaining weight or 0.

heap priority-queue simulation

Linked Lists easy

Read the tail node value

Return the last value or None when the list is empty.

linked-list lists pointers

Linked Lists medium

Append a new tail

Add value after the last node.

linked-list lists pointers

Linked Lists medium

Pairwise sum of adjacent nodes

Sum each adjacent pair; keep a lone last node as-is.

linked-list lists pointers

Linked Lists hard

Drop the tail node

Return a new list without the last node.

linked-list lists pointers

Datetime & Time Calculations easy

Month End Date

Implement a function that returns the last day of the month for a given year and month.

datetime calendar leap-year

Datetime & Time Calculations medium

Easter Date Calculator

Implement a function that returns the date of Easter Sunday for a given year using the Gregorian computus algorithm.

datetime date easter

Showing 25–36 of 36 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.