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467 challenges 330 easy 120 medium 17 hard

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Dicts & Sets easy

First non-repeating character

Find the index of the first character that appears only once.

dict strings counter

Dicts & Sets easy

Word to Index Map

Create a function that returns a dictionary mapping each unique word to the index of its first occurrence.

dictionary mapping indexing

Dicts & Sets easy

Pair with difference K

Count unordered index pairs with absolute difference exactly K, handling duplicates correctly.

dictionary set counting

Showing 3 challenges · Dicts & Sets

Dicts & Sets — Python coding challenges

What you will find here

This page lists dicts & sets 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.