DSAAnimator
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185+ top-asked problems · animated step by step

Stop memorizing DSA. Watch how it works, watch it think, watch it click.

DSA Animator is a DSA visualizer where every problem plays like a film. Pointers glide, arrays shift, trees grow, and the exact line of Java lights up beside each move. Pause it. Rewind it. Feed it your own input. That's when it finally clicks.

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  • 43 patterns, animated
  • Java + Python solutions
  • New content added continuously
11 · Container With Most Water Medium Two Pointers

    Your next “MAANG” offer is one click away.

    Start free today. Keep the free lessons forever.

    Start free with Google Browse all DSA animations

    Playground

    Don’t take our word for it.
    Break an algorithm yourself.

    Change the input, click the nodes, scrub the timeline. Every lesson on DSA Animator works just like this.

      The moment it clicks

      You’ve read “reverse a linked list” ten times.
      Now watch every word of it happen.

      The textbook version · follow along

      Initialize pointers prev = null and curr = head. Iterate while curr is not null: store curr.next in next, point curr.next back to prev, advance prev to curr and curr to next. When the loop ends, prev is the new head.

        Inside every problem

        Not a video. Not a wall of text.
        A lesson you can drive.

        1. 1

          The real problem, not a paraphrase

          Statement, constraints and worked examples, straight from the LeetCode problem you’ll meet in interviews.

        2. 2

          Your input, your edge cases

          Switch examples or type your own array and watch the algorithm handle it. Break it on purpose.

        3. 3

          Every step, at your pace

          Play, pause, step back, change speed. Nothing is hidden between “input” and “output”.

        4. 4

          Code in lockstep with the picture

          The running line highlights as the visual moves, in Java or Python, with time and space complexity spelled out.

        5. 5

          Progress that follows you

          Mark problems solved, bookmark the tricky ones, keep private notes, synced across devices.

        Beyond DSA

        The rest of the interview loop,
        built with the same obsession.

        System Design

        85 topics, HLD to LLD

        SOLID, GoF patterns, concurrency, databases, Kafka and full low-level designs (Parking Lot, BookMyShow, Splitwise) with class diagrams and Java.

        Explore designs →
        Code Tricks · Edge Cases · Quiz

        The small things that fail interviews

        Compact code idioms you’ll reuse in every round, topic-wise edge-case checklists, and a timed quiz that trains you to spot the right pattern fast.

        Sharpen up →
        Scenario Questions

        45 senior-loop scenarios

        Double payments, cache stampedes, Kafka exactly-once. Answered the way SDE-2 and senior interviewers expect.

        Read answers →
        Java Interview

        286 Java & Spring questions

        Core Java, collections, multithreading, JVM, Spring Boot, JPA and security, tagged by level from fresher to experienced.

        Start revising →
        Jobs

        Product-company roles, refreshed 2×/day

        Pulled from official career pages, not reposted spam. Filter by company, country and remote.

        See open roles →

        Pricing

        One price. Everything unlocked.
        Then pay once. No renewals.

        One payment unlocks every feature for the period you choose. No auto-renewal, no ads, no surprises.

        Every plan unlocks everything

        Full access to every feature. Plans only differ in how long you keep it.

        • 185+ top-asked DSA problemsStep by step, Java & Python
        • 43 DSA patterns37 animated pattern walkthroughs
        • Code tricksIdioms you’ll reuse in every round
        • Edge-case checklistsTopic-wise, so nothing surprises you
        • Pattern quizTimed questions with explanations
        • 85 system design topicsHLD, LLD, SOLID & design patterns
        • 45 scenario interview questionsFor SDE-2 and senior loops
        • 286 Java & Spring questionsFresher to experienced
        • Jobs boardProduct-company roles, refreshed 2×/day
        • Every new updateNew problems & questions, continuously

        Free account

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        forever

        • Free animated problems
        • Previews of every section
        • Progress, bookmarks & notes sync
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        Monthly

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        for 1 month

        • Everything above, unlocked
        • All updates during your plan
        • One-time payment
        Get started
        Recommended for interview prep

        Quarterly

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        for 3 months

        • Everything above, unlocked
        • A full interview-prep cycle
        • All updates during your plan
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        Yearly

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        for 12 months

        • Everything above, unlocked
        • Lowest monthly cost
        • A full year of new content
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        Prices shown for your region. The AI-Powered Java Backend course is sold separately.

        Always shipping

        DSA Animator is never “finished”.
        New questions and features, continuously.

        We keep adding problems, animations and interview questions, and keep polishing the app. Every update is included in your plan at no extra cost. Here’s what shipped recently.

        1. Rebuilt, smoother animations

          Re-crafted linked-list and sorting visualizations, plus pricing for learners outside India.

        2. 286 Java interview questions

          Scenario-based interview questions and a mobile-friendly redesign.

        3. Low-level design library

          Parking Lot, BookMyShow, Splitwise and more, with class diagrams and Java.

        4. System Design & Jobs

          85 topics from HLD to LLD, and product-company roles refreshed twice a day.

        5. Progress, notes & quiz

          Mark problems solved, keep private notes, and test your pattern instinct.

        More problems, patterns and interview questions are already on the way.

        What learners say

        The “oh, that’s why” moment.

        “I always struggled to understand what was actually happening inside an algorithm. The animations on DSA Animator make things much easier to visualize, especially trees, graphs and sorting algorithms.”
        Rahul MehtaDSA Animator learnerTrees & Graphs
        “The visual approach is what stood out to me. Some DSA topics that felt confusing from YouTube tutorials became much clearer after watching the animations.”
        Aditya KulkarniDSA Animator learnerVisual learning
        “I've been working as a software engineer for a few years, and I honestly wish I had something like this when I was preparing for interviews. Seeing the algorithm execute visually makes the concepts much easier to retain.”
        Daniel CarterDSA Animator learnerInterview prep
        “What I like most is that DSA Animator focuses on understanding instead of just memorizing solutions. It's been useful for brushing up on algorithms before technical interviews.”
        Michael ChenDSA Animator learnerInterview refresh
        “As someone preparing for software engineering interviews while working full-time, I don't have hours to spend on every topic. The visual explanations help me understand concepts quickly and get back to solving problems.”
        Olivia BrownDSA Animator learnerWorking professional
        “As a student preparing for placements, this has been really useful. Instead of repeatedly reading the same DSA explanation, I can actually see how the algorithm works step by step.”
        Priya SharmaDSA Animator learnerPlacement prep
        “I use DSA Animator while preparing for coding interviews and it has become one of my regular practice resources. The pattern-based approach is especially helpful when I am stuck on a problem.”
        Sneha PatilDSA Animator learnerPatterns
        “The animations are simple but very effective. I can understand the flow of an algorithm much faster than when I only look at code and static diagrams.”
        Sophie MartinDSA Animator learnerAlgorithm flow
        “I've tried a lot of DSA resources, but the visualizations here give the learning experience a completely different feel. Graphs and tree problems especially make much more sense visually.”
        James WilsonDSA Animator learnerTrees & Graphs
        “This is one of those platforms where you can immediately see why an algorithm works instead of just memorizing the code. The interactive and animated approach makes DSA much more engaging.”
        Lucas AndersonDSA Animator learnerInteractive learning

        FAQ

        Questions, answered.

        What is DSA Animator?

        DSA Animator is a DSA animation and visualization platform for coding interview prep. Each of its 185+ top-asked LeetCode problems runs as a step-by-step animation with the Java or Python code highlighted in sync, so you learn DSA with animation instead of memorizing solutions.

        What is a DSA visualizer, and does it really help?

        A DSA visualizer shows every intermediate state of a data structure or algorithm, like pointers moving, a window sliding or a tree being built, instead of only the final answer. That kind of DSA visualization makes it much easier to understand why a solution works and to explain it in an interview.

        How is this different from LeetCode or YouTube?

        LeetCode gives you the problem and a verdict; a video moves at someone else’s pace. DSA Animator shows every intermediate state of the algorithm, synced to the code, and lets you step, rewind and change the input. You see why the solution works, not just that it does.

        Is new content still being added?

        Yes, continuously. Recent months added the system design and LLD library, 286 Java interview questions, scenario-based questions and rebuilt animations, and more problems, patterns and questions are on the way. Every update is included in your plan.

        Do I need to be good at DSA already?

        No. Topics start from basics (arrays, prefix sums, two pointers) and every problem is tagged easy, medium or hard, so you can build up at your own pace. If you’re already strong, the hards and patterns sharpen your intuition fast.

        Which languages are the solutions in?

        Animated lessons include solutions in Java and Python, with time and space complexity for each approach.

        Is the subscription a recurring charge?

        No. It’s a one-time payment for the period you pick. Nothing renews or gets debited automatically.

        Why charge at all?

        So we never run ads or sell your attention. Memberships fund new animations, new topics and a faster, cleaner product.

        Start free