Valid parentheses
Return True if brackets in the string close in the correct order.
Previous Smaller Element
Find the nearest previous index with a smaller value for every element in an array.
Next greater element II
For each element in a circular array, find the next greater element (NGE) to its right, wrapping around.
Largest Rectangle in Histogram
Given an array of bar heights, compute the largest rectangle that can be formed by consecutive bars.
Basic Calculator II
Evaluate a basic arithmetic expression with +, -, *, / following operator precedence.
Online Stock Span
Implement StockSpanner.next(price) that returns the maximum number of consecutive days (including today) with price <= current price.
Design Browser History
Implement a BrowserHistory class that supports visit, back, and forward navigation with step counts.
Largest Area Histogram Matrix
Given a binary matrix, compute the largest rectangle area consisting entirely of 1s.
Showing 1–8 of 8 challenges · Data Structures & Algorithms
Data Structures & Algorithms — Python coding challenges
What you will find here
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.
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.