Longest Consecutive Sequence
Given an unsorted list of integers, find the length of the longest consecutive elements sequence in O(n) time.
Pascal Triangle Row
Given a non-negative integer n, return the nth row of Pascal's triangle as a list of integers.
Radix Sort
Implement LSD radix sort to sort a list of non-negative integers in ascending order.
Find Peak Index
Given a list of integers, return the index of any peak element where the value is not smaller than its neighbors.
Peak Element in Array
Implement a function that returns the index of any peak element in a list of integers.
Argsort Indices
Implement a function that returns the indices that would sort a list of integers, with ties broken by original order.
Arithmetic Slices Count
Given a list of integers, count how many contiguous subarrays of length at least 3 form an arithmetic sequence.
Showing 1–7 of 7 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.