⚡ DSA Solutions & Visual Explorer

Comprehensive JavaScript solutions for classic DSA questions combined with a premium interactive web-based visual explorer.

🌐 Live Demo: https://dsa-solutions-ten.vercel.app/

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📸 Demo

Dijkstra's shortest path with live distance table updates

Segment Tree range query with overlap highlighting

Full keyboard shortcut support for hands-free learning

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📸 Interactive Visual Explorer

The repository contains a custom web application located in the /visualizer directory. It uses HTML5 Canvas and an interactive step-by-step frame-animation engine to display the mechanics of algorithms in real-time.

🎮 Custom Animation Pipeline Controls

Our custom animation engine supports full playback controls:

• Play/Pause (⏸ / ▶): Toggle active playback.
• Step Forward (⏭): Step animation index forward by 1 frame.
• Step Backward (⏮): Step animation index backward by 1 frame.
• Reset (🔄): Resets frame index to 0 and redraws the initial setup.
• Speed Slider: Dynamically divides the frame timeout delay (range: 0.25x to 4x).

⌨️ Keyboard Shortcuts

• Enter: Run the current algorithm with selected inputs.
• Escape:
  • If viewing an algorithm runner ➔ return to the topic detail page.
  • If viewing a topic detail page ➔ return to the home screen.

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🚀 Quick Start

Prerequisites

• Node.js: version 18.0.0 or higher.
• Browser Compatibility: Modern browsers (Chrome 90+, Firefox 88+, Safari 14+, Edge 90+) supporting HTML5 canvas and rounded rectangles.

Running CLI Solutions

Run any solution file using Node.js directly:

# Run Graph algorithms
node 12_graphs/graphs.js

# Run Segment Tree algorithms
node 16_segment_tree/segment_tree.js

Launching the Web Visualizer

To run the interactive visualizer locally:

1. Navigate to the visualizer directory:

   cd visualizer

2. Spin up a local development web server:

   # Python (standard installation)
   python -m http.server 8080
   
   # Node/NPM (one-click dev server)
   npx serve .

3. Open http://localhost:8080 in your web browser.

💡 Or skip local setup entirely — use the live deployment at https://dsa-solutions-ten.vercel.app/

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📚 Master Index & Study Resources

• Master Solutions Index: A complete list of implemented algorithms, complexities, difficulties, and file paths.
• Algorithmic Design Patterns: Solutions categorized by standard design patterns (Two Pointers, Sliding Window, Monotonic Stack, etc.).
• FAANG Company Mapping: Frequent interview questions from Google, Meta, Amazon, and Microsoft mapped to code solutions.
• Complexity Cheat Sheet: Access, search, insert, and delete complexities for all data structures and sorting algorithms.
• Technical Interview Strategy: Whiteboard strategies, dry running procedures, clarification checklists, and time allocation templates.
• System Design Basics & DSA: Bridges data structures (Skip Lists, B-Trees, Tries) to distributed architectures (LSM Trees, Consistent Hashing, LRU Caches).

Folder Structure & Categories

• 01_basic_math: Primality checks, factorials, digit counting, and basic number logic.
• 02_patterns: Geometric pattern rendering, pyramids, diamonds, checkerboards, and Pascal's Triangle.
• 03_strings: Palindrome checks, anagram validations, reversals, and character frequencies.
• 04_arrays: Sums, min/max values, rotations by K elements, and sorted array merging.
• 05_searching: Linear, binary, and rotated search implementations.
• 06_sorting: Bubble, Selection, Insertion sort, and Dutch National Flag partition.
• 07_recursion: Tower of Hanoi simulation, subsets generation, and recursive math helpers.
• 08_data_structures: Linked Lists (insertion, deletion, middle nodes, reversals) and Array-based Stacks & Queues.
• 09_advanced_patterns: Sliding Window bounds and Two-Pointer paradigms (e.g., 3Sum).
• 10_advanced_misc: Matrix sorting, Catalan numbers, postfix expressions evaluation, and first missing positive.
• 11_trees: DFS Traversals (inorder/preorder/postorder), BFS Traversals (level-order traversal), tree height, BST validation, and mirroring.
• 12_graphs: Adjacency list implementation, BFS, DFS, shortest path in unweighted graphs, and Dijkstra's Algorithm for weighted graphs.
• 13_dynamic_programming: Memoized Fibonacci, 0/1 Knapsack, Longest Common Subsequence (LCS), and Min Coin Change.
• 14_heaps_trie: Min-Heap bubble-up/down logic and Trie (Prefix Tree) inserts/searches.
• 15_bit_manipulation: Bit get/set/clear/update operations, powers of two checks, Hamming Weight (set bits count), and XOR single number.
• 16_segment_tree: Range Sum Query and Point Update segment tree implementation.
• 17_backtracking: N-Queens, Sudoku Solver, and Permutations.
• 18_greedy: Activity Selection, Fractional Knapsack, and Jump Games.
• 19_union_find: DSU class implementation, cycle detection, and Kruskal's Minimum Spanning Tree.
• 20_monotonic_stack: Next Greater Element, Largest Rectangle in Histogram, and Trapping Rain Water using monotonic stack designs.
• blind_75: Highly optimized solutions for standard Blind 75 questions categorized by type (Array, Binary, DP, Graph, etc.).

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🤝 Contributing

Contributions are welcome! Please see visualizer/README.md to understand the architecture, state transition flow, and step-by-step instructions on how to add new algorithms or visualizers.

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📄 License

This project is licensed under the MIT License — see the LICENSE file for details.