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

Linked Lists medium

Prepend a new head

Insert value at the front of the list.

linked-list lists pointers

Linked Lists medium

Append a new tail

Add value after the last node.

linked-list lists pointers

Linked Lists medium

Palindrome linked values

Check whether values read the same forwards and backwards.

linked-list lists pointers

Linked Lists medium

Rotate list left by k

Move the first k nodes to the end (k may exceed length; use modulo).

linked-list lists pointers

Linked Lists medium

Merge two sorted lists

Merge two ascending integer lists into one sorted list.

linked-list lists pointers

Linked Lists medium

Remove duplicate values

Keep first occurrence of each value while preserving order.

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 medium

Count nodes equal to target

Count how many times target appears in the list.

linked-list lists pointers

Linked Lists medium

Zip two linked lists

Interleave values from a and b until both are exhausted.

linked-list lists pointers

Linked Lists medium

Split list at index

Return prefix and suffix tuples at index k.

linked-list lists pointers

Showing 25–34 of 34 challenges · medium

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.