Modern Tower of Hanoi in Flutter

Introduction:

The Tower of Hanoi puzzle is a staple in computer science, known for its elegant recursive solution. But what if you could not only understand this classic problem but also visualize its solution interactively? This blog takes you through building a Tower of Hanoi app using Flutter, combining algorithmic insight with engaging user interaction.

This project demonstrates how to implement a fundamental algorithm with Flutter's expressive UI capabilities, making it both educational and visually appealing. You can find the full source code and more on my GitHub Repository.

Why the Tower of Hanoi?

The Tower of Hanoi puzzle is an excellent introduction to recursion and problem-solving techniques. Despite its simplicity, it offers profound insights into recursive problem-solving, making it an ideal candidate for mobile app development. My goal was to build an app that not only solves the puzzle but also demonstrates the recursive algorithm visually, making it accessible to both beginners and experienced developers.

Tools and Technologies:

This project leverages the power of Flutter, a framework designed for building beautiful, fast, and natively compiled applications. By combining the capabilities of Dart with Flutter’s interactive UI components, I created a smooth and responsive experience. Here’s a look at the tools I used:

Flutter: The go-to framework for cross-platform mobile apps, enabling development for both Android and iOS with a single codebase.
Dart: The language behind Flutter, which is concise, fast, and perfect for implementing recursive algorithms.
Custom Widgets: Flutter's flexibility allowed me to build custom UI elements to represent pegs, disks, and the interactive gameplay board.
Animation: Smooth and visually appealing animations were essential to make the puzzle-solving process both engaging and educational.

Key Features of the App:

Interactive Puzzle Board: Users can drag and drop disks between pegs, solving the puzzle manually. The board dynamically adjusts based on the number of disks, providing an immersive hands-on experience.
Automated Solution Animation: For users unfamiliar with the recursive algorithm, the app includes an auto-solve feature. It demonstrates the step-by-step solution, animating each disk movement, allowing users to visualize the recursive process in real-time.
Adjustable Difficulty: Players can select the number of disks, with the difficulty increasing as more disks are added. This makes the app suitable for users of all skill levels, from beginners to experienced solvers.
Step-by-Step Visualization: For learners, the app breaks down the recursive solution into digestible steps. Each recursive call is visually represented, reinforcing the algorithm's logic.

The Code Behind the Puzzle:

At the heart of the Tower of Hanoi puzzle is its recursive solution. Here’s how I approached the code:

Recursive Algorithm: The recursive approach divides the problem into smaller subproblems by moving the disks between pegs, one at a time, while adhering to the puzzle’s constraints. The key to solving the puzzle lies in moving n-1 disks to an auxiliary peg, then moving the nth disk to the target peg, and finally moving the n-1 disks from the auxiliary peg to the target peg.
UI Design and Interactivity: I built a highly interactive user interface where users can directly manipulate the disks. By using Flutter's custom widgets, I ensured that each disk is draggable and positioned correctly, while keeping the interface clean and intuitive.
Animations: To add a layer of engagement, I implemented smooth animations using Flutter’s animation library. Each disk moves fluidly between pegs, creating an enjoyable visual experience while demonstrating how the recursive algorithm unfolds.
State Management: The game’s state, including the current positions of disks, the number of disks, and the game status (whether the puzzle is solved or not), is managed using Flutter’s StatefulWidget and setState(). This ensures that the UI stays up-to-date and responsive to user interactions.

Overcoming Challenges:

Creating this interactive app presented some challenges:

Recursive Visualization: One of the main challenges was visualizing the recursive nature of the puzzle in a way that is intuitive to users. I implemented smooth animations and controlled the timing of each recursive step to ensure users could follow along with the solution process without feeling overwhelmed.
Performance Optimization: Handling high disk counts could lead to performance issues, particularly when animating multiple disks at once. I optimized the app by ensuring that only the necessary animations were triggered and used efficient rendering techniques to handle larger numbers of disks smoothly.
Responsive UI: Ensuring the app’s UI was responsive to user input, especially on different screen sizes and resolutions, required careful design. I used Flutter’s layout and design tools to ensure the app scaled properly, maintaining both usability and aesthetics.

What’s Next? Enhancements & Future Ideas:

While the current version of the app is fully functional, here are some future enhancements I plan to implement:

Dark Mode: Adding a dark mode theme for a more customizable and modern user experience.
Timed Mode: A competitive timed mode where users can race against the clock to solve the puzzle and compare their times with others.
Hints and Smart Suggestions: Introducing an intelligent hint system that can provide guidance to users who get stuck, without giving away the entire solution.
Level Progression: Allowing users to unlock new levels or challenges based on the number of disks solved, adding replay value to the app.
Social Features: Integration with social media platforms, allowing users to share their best times or challenge friends.

Conclusion:

Building the Tower of Hanoi puzzle app using Flutter has been an incredibly rewarding journey. Not only did I learn how to effectively implement a recursive algorithm, but I also gained valuable insights into mobile UI/UX design and animation. By visualizing the solution and providing an interactive experience, this app offers a fun and educational way to understand the power of recursion.

I hope this project inspires you to explore algorithmic challenges and create your own mobile apps using Flutter. You can find the complete source code and contribute to future improvements on my GitHub Repository.

Call to Action:

If you’ve enjoyed this post or have any feedback, feel free to leave a comment below! I’d love to hear your thoughts and any ideas you have for future enhancements. Don’t forget to share your own projects and join the conversation.

Tags:

Flutter, Dart, Mobile Development, Tower of Hanoi, Recursive Algorithms, Puzzle Games, Algorithm Visualization, App Development, Game Development, Programming

This version is designed to be more engaging and professional, emphasizing the educational and interactive nature of the project while showcasing the technical details in a structured and appealing way. The aim is to capture the reader’s interest by making the post informative, visually attractive, and easy to follow, while encouraging feedback and interaction.

Solving the Tower of Hanoi Puzzle with Flutter: A Modern Take on an Ancient Algorithm