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467 challenges 330 easy 120 medium 17 hard

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Lists & Arrays easy

Running Product of Integers

Given a list of integers, return a new list where each element at index i is the product of all elements from index 0 to i.

prefix product lists

Lists & Arrays easy

Rotate Left by k

Implement a function that rotates a list left by k positions.

rotation lists slicing

Lists & Arrays easy

Interleave Two Lists

Write a function that interleaves two lists element by element, preserving order.

lists merge indexing

Lists & Arrays easy

Keep only even indexes

Given a list, return a new list containing only the elements at even indices (0, 2, 4, ...).

list slicing indexing

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

Lists & Arrays easy

Zip lists into pairs

Write a function that takes two lists and returns a list of two-element sublists pairing elements by index up to the shortest length.

zip lists pairs

Lists & Arrays easy

Middle Element of an Odd-Length List

Implement a function that returns the middle element of an odd-length list.

lists indexing basic

Lists & Arrays easy

Zip Two Lists

Write a function that pairs elements from two lists by index, stopping at the shorter list.

zip lists pairs

Lists & Arrays easy

Last occurrence index

Implement a function that returns the last index of a given value in a list, or -1 if the value is not present.

lists indexing search

Showing 9 challenges · 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.