Top N per group
Implement top_n_per_group that returns the top N scores for each group from a list of (group, score) pairs.
Consecutive available seats
Given a list of seat statuses, return the length of the longest consecutive run of available (0) seats.
Argsort Indices
Implement a function that returns the indices that would sort a list of integers, with ties broken by original order.
Level Order Traversal
Implement a function that performs a level order traversal of a binary tree and returns node values as a list of lists.
Matchsticks to Square
Given a list of matchstick lengths, decide if they can form a square by using each matchstick exactly once.
Merge K Sorted Lists
Write a function that merges multiple sorted lists into a single sorted list.
Memory view slice
Implement chunk_list that splits a list into consecutive sublists of a given chunk size.
Delete Middle Node
Implement a function that deletes a given non-tail node from a singly linked list in O(1) time.
Design Skip List Lite
Implement a simplified skip list supporting insert, search, and delete with O(log n) average complexity.
Delete duplicates sorted II
Given a sorted list, remove duplicates in place so each element appears at most twice, returning the new length.
Arithmetic Slices Count
Given a list of integers, count how many contiguous subarrays of length at least 3 form an arithmetic sequence.
Accounts Merge
Given a list of accounts, merge those that share any email and return sorted accounts.
Showing 25–36 of 36 challenges · Data Structures & Algorithms
Data Structures & Algorithms — Python coding challenges
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This page lists data structures & algorithms 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.
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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.