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467 challenges 330 easy 120 medium 17 hard

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Lists & Arrays easy

Second Largest Unique Value

Return the second largest distinct integer from a list, or None if it doesn't exist.

sorting unique arrays

Lists & Arrays easy

Find Missing Number 1 to n

Given a list containing n-1 distinct integers from 1 to n, find the missing number without using extra space.

arrays math search

Lists & Arrays easy

Union of Two Lists

Implement a function that combines two lists and returns only unique elements.

Showing 3 challenges · easy · Lists & Arrays

Lists & Arrays — Python coding challenges

What you will find here

This page lists lists & arrays 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.