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467 challenges 330 easy 120 medium 17 hard

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Lists & Arrays medium

Merge intervals

Merge all overlapping intervals and return a sorted result.

Lists & Arrays medium

Product except self

Return an array where output[i] is the product of all elements except nums[i], without using division.

arrays prefix-sum

Lists & Arrays medium

Product of All Except Zeros Handling

Given a list of integers, return a list where each element is the product of all other elements, handling zeros correctly.

product arrays zero-handling

Lists & Arrays medium

Partition around a pivot value

Implement an in-place partition of a list around a given pivot value, returning the boundary index.

lists partition two-pointer

Showing 4 challenges · medium · 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.