Maintenance

Site is under maintenance — quizzes are still available.

Sponsored Reserved space — layout preview until AdSense is connected

Practice Arena

Python Coding
Challenges

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

56 challenges 25 easy 23 medium 8 hard

All Easy Medium Hard

Sponsored Reserved space — layout preview until AdSense is connected

All Python Basics Strings & Text Lists & Arrays Dicts & Sets Functions & Closures OOP & Classes Data Structures & Algorithms Advanced Python

Strings & Text medium

Run-length encoding

Compress consecutive identical characters, e.g. 'aaabbc' → 'a3b2c1'.

strings compression

Strings & Text medium

Longest common prefix

Find the longest common prefix among a list of strings.

Strings & Text medium

Integer to Roman

Convert a positive integer to its Roman numeral representation.

Strings & Text medium

Zigzag string conversion

Encode a string in zigzag order across numRows rows, then read row by row.

Showing 4 challenges · medium · filtered by category