📘 Java Data Structures Course – Round 2

Welcome to the official repository for the Java Data Structures Course – Round 2 🎉.
This course is another hands-on journey into data structures with Java, starting from zero with fresh explanations, examples, and exercises.

Whether you’re just beginning your path or looking for a clean restart, this round is built to give you solid foundations step by step.

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🧠 What You’ll Learn

• 📦 ArrayList – dynamic arrays and internal logic
• 🔗 LinkedList – singly and doubly linked lists
• 🧱 Stack – LIFO behavior with use cases
• 📬 Queue – FIFO, circular queues, and variations
• 🧮 Recursion – single, double, and backtracking
• 🗃️ HashMap & HashSet – hashing fundamentals
• 🌲 Trees – binary trees, traversals, and BSTs
• 🕸️ Graphs – adjacency list, BFS, DFS, and basic pathfinding
• 🧩 Problem Solving – multiple coding problems for each structure

🔧 Each data structure includes:

• A full Java implementation from scratch
• A main class for quick testing
• A Problems class for practice

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📁 Project Structure

📦 data_structures_course_round2/
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├── 📁 arraylist/         # Implementations + beginner problems
├── 📁 linkedlist/        # Singly/Doubly Linked List basics
├── 📁 stack/             # Stack implementation + practice
├── 📁 queue/             # Queue + Circular Queue examples
├── 📁 hashmap_hashset/   # Intro to HashMap & HashSet
├── 📁 recursion/         # Simple recursion exercises
├── 📁 trees/             # Basic Binary Tree + traversals
├── 📁 graphs/            # Adjacency List + BFS/DFS
├── 📁 problems/          # Extra beginner problems
└── 📄 README.md          # Course overview and instructions