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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

Repeat each character n times

Given a string s and an integer n, return a new string where each character of s is repeated n times consecutively.

strings join comprehension

Strings & Text easy

Remove Consecutive Duplicate Letters

Implement a function that removes consecutive duplicate letters from a string, keeping only one occurrence of each run.

strings loops manipulation

Strings & Text easy

Remove Duplicates from String

Given a string, return a new string with each character that repeats consecutively reduced to a single occurrence.

strings loop filter

Strings & Text easy

Count Syllables (Simple)

Count syllables in a word by counting groups of consecutive vowels (a, e, i, o, u).

strings vowels counting

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

Validate username format

Implement a function that validates a username according to length, allowed characters, and no consecutive underscores.

strings validation returns

Showing 7 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.