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Python Coding
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791 challenges 498 easy 262 medium 31 hard

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Lists & Arrays easy

Remove duplicates (sorted)

Return a sorted list with duplicates removed.

arrays two-pointer

Lists & Arrays easy

Merge two sorted arrays

Merge two sorted arrays into one sorted array.

arrays merge two-pointer

Lists & Arrays easy

Insert into a Sorted List

Implement a function that inserts a value into a sorted list at the correct position using binary search.

lists binary-search insertion

Lists & Arrays easy

Intersection of Two Lists

Given two lists, return a sorted list of unique elements that appear in both lists.

intersection sorting unique

Lists & Arrays easy

Merge Sorted Array In Place

Write a function that merges two sorted arrays into the first array in-place, keeping the result sorted.

arrays sorting in-place

Lists & Arrays easy

Cartesian Product Pairs

Create a function that returns the Cartesian product of two lists as a sorted list of lists.

lists tuples sorting

Showing 6 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.