🚀 Java DSA & OOPS Complete

A comprehensive collection of 79+ Java programs covering Java Basics, Data Structures & Algorithms (DSA), and Object-Oriented Programming (OOP) concepts — perfect for beginners and interview preparation! 🎯

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📚 Topics Covered

Category	Topics
Basics	Variables, I/O, Conditionals, Loops, Functions, Pattern Printing
DSA	Arrays, Strings, Sorting, Recursion, Searching, 2D Arrays
OOP	Classes, Objects, Inheritance, Polymorphism, Abstraction

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📁 Folder Structure

java-dsa-oops/
├── BASICS/                    # Core Java fundamentals
│   ├── functions_methods/
│   └── loops/
├── DSA/                       # Data Structures & Algorithms
│   ├── ArrayList/
│   ├── Backtracking/
│   ├── BinaryTree/
│   ├── Greedy/
│   ├── LeetCode/
│   ├── Linkedlist/
│   ├── QUEUE/
│   ├── Stack/
│   ├── arrays/
│   ├── codeforces/
│   ├── recursion/
│   ├── sorting/
│   └── strings/
├── basics/                    # Core Java fundamentals (duplicate/lowercase)
│   ├── functions_methods/
│   └── loops/
├── dsa/                       # Data Structures & Algorithms (duplicate/lowercase)
│   ├── ArrayList/
│   ├── Backtracking/
│   ├── LeetCode/
│   ├── Linkedlist/
│   ├── arrays/
│   ├── codeforces/
│   ├── recursion/
│   ├── sorting/
│   └── strings/
├── gfgQues/                   # GeeksforGeeks Questions
└── oops/                      # OOP concepts & examples

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⚡ Quick Start

Prerequisites

• Java JDK 8 or higher

Run any program

# Clone the repository
git clone https://github.com/utkarsh232005/Java-DSA-OOPS-Complete.git
cd Java-DSA-OOPS-Complete

# Compile and run (example: recursion problem)
cd dsa/recursion
javac Consecativeones.java
java Consecativeones

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🗂️ What's Inside

📘 basics/ — Java Fundamentals

File	Description
hello.java	Hello World
calculator.java	Basic calculator
leapYear.java	Leap year checker
loops/pattern.java	Pattern printing
functions_methods/factorial.java	Factorial using functions

📗 dsa/ — Data Structures & Algorithms

Folder	Programs
arrays/	Binary Search, Linear Search, Max Subarray, Trapped Water, Reverse Array
arrays/two_d/	Spiral Matrix, 2D Array Operations
sorting/	Bubble Sort, Selection Sort, Insertion Sort, Count Sort
strings/	Palindrome, String Compression, Substring, Shortest Path
recursion/	Consecutive Ones, Friends Pairing, Tiling Problem

📕 oops/ — Object-Oriented Programming

File	Concepts
OOPS.java	Classes, Objects, Inheritance, Polymorphism
abstraction.java	Abstract classes & methods

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🎯 Great For

• ✅ Java beginners learning fundamentals
• ✅ DSA interview preparation (FAANG, product companies)
• ✅ College students & CS coursework
• ✅ Competitive programming practice
• ✅ Quick reference & revision

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🤝 Contributing

Contributions are welcome! Feel free to:

• Add new programs
• Fix bugs or improve existing code
• Add comments/documentation

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⭐ Show Your Support

If this repo helped you, please give it a star ⭐ — it helps others find it too!

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📬 Connect

Made with ❤️ by Utkarsh

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🏷️ Topics

java dsa data-structures algorithms oops object-oriented-programming java-programming beginner-friendly interview-preparation leetcode sorting-algorithms recursion arrays strings competitive-programming learn-java java-basics coding-practice programming