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All practice problemsCoding, design and hands-on challenges.Repository CodingHands-onFix bugs and build in a real codebase.Code ReviewHands-onFind risks and explain your verdict.Data structures & algorithmsCore patterns to advanced algorithms.Machine learningImplement ML and numerical methods.SQL & databasesQueries, data and analytical problems.HLD system designScalable architecture and tradeoffs.LLD system designObjects, interfaces and behavior.GATE papersBranch-wise previous year papers and worked solutions.AptitudeAptitude topics and exam practice.AI interview prepRehearse interviews with an AI tutor.Online compilerWrite and run code in your browser.

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Learning pathsConnect lessons, visualizers and practical challenges.Algorithm visualizersStep through algorithms and see how they work.ReadingRead books, notes and research papers with AI.Daily current affairsUnderstand the news, save notes and revise the brief.Data structures & algorithmsLearn the foundations of efficient problem solving.Machine learningBuild mathematical intuition and explore ML concepts.SQL & databasesUnderstand data models, queries and transactions.System designStudy architecture, distributed systems and object design.
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THE PRACTICE LIBRARY

One place. Every way to practice.

Choose the skill you want to build. Find a focused challenge, work through it, and make your next attempt count.

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Data structures & algorithmsSQL & databasesMachine learningHigh-level system designLow-level system designRepository codingCode review

SQL & databases

Build a working understanding of relational data. Practice accurate queries, reason about database behavior, and learn how a good data model supports a good application.

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Keep your practice and learning days together across every subject.