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467 challenges 330 easy 120 medium 17 hard

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Strings & Text medium

Run-length encoding

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

strings compression

Strings & Text easy

Compress Consecutive Chars

Write a function that compresses a string by replacing runs of identical characters with the character followed by the count.

string run-length compression

Strings & Text easy

Expand compressed string

Implement a function that expands run-length encoded strings (e.g., 'a3b2' → 'aaabb').

strings parsing run-length-encoding

Showing 3 challenges · Strings & Text

Strings & Text — Python coding challenges

What you will find here

This page lists strings & text challenges — real Python problems you solve in the browser IDE with instant test feedback. Each challenge includes a clear brief, starter code, and automated checks.

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.