LeetLab 🚀

A modern online coding platform that allows users to write, compile, and execute code in multiple programming languages with real-time feedback.

🌟 Features

• Multi-language Support: Write and execute code in Java, C++, JavaScript, and Python
• Real-time Code Execution: Powered by Judge0 API for fast and secure code compilation
• User Authentication: Custom-built login/signup system with secure session management
• Clean UI: Modern, responsive interface built with React
• Code Editor: Syntax highlighting and auto-completion for better coding experience
• Test Cases: Run your code against custom input/output test cases
• Results Dashboard: View execution time, memory usage, and output results

🛠️ Tech Stack

Frontend:

• React.js
• HTML5/CSS3
• JavaScript (ES6+)
• Responsive Design

Backend:

• Node.js/Express.js (or your backend tech)
• RESTful APIs
• JSON Web Tokens (JWT) for authentication
• bcrypt for password hashing

External APIs:

• Judge0 API for code compilation and execution

Database:

• MongoDB/PostgreSQL (specify your choice)

📁 Project Structure

leetlab/
├── frontend/           # React application
│   ├── src/
│   │   ├── components/
│   │   ├── pages/
│   │   ├── utils/
│   │   └── App.js
│   ├── public/
│   └── package.json
├── backend/            # Server application
│   ├── controllers/
│   ├── models/
│   ├── routes/
│   ├── middleware/
│   └── server.js
└── README.md

🚀 Getting Started

Prerequisites

• Node.js (v14 or higher)
• npm or yarn
• Judge0 API key (get it from Judge0)

Installation

1. Clone the repository

   git clone https://github.com/rohittrana/leetlab.git
   cd leetlab

2. Setup Backend

   cd backend
   npm install

   Create a .env file in the backend folder:

   PORT=5000
   MONGODB_URI=your_mongodb_connection_string
   JWT_SECRET=your_jwt_secret_key
   JUDGE0_API_KEY=your_judge0_api_key
   JUDGE0_HOST=judge0-ce.p.rapidapi.com

3. Setup Frontend

   cd ../frontend
   npm install

4. Start the Application

   Start backend server:

   cd backend
   npm start

   Start frontend (in new terminal):

   cd frontend
   npm start

5. Access the Application

   • Frontend: http://localhost:3000
   • Backend API: http://localhost:5000

🎯 How to Use

1. Sign Up/Login: Create an account or login with existing credentials
2. Choose Language: Select from Java, C++, JavaScript, or Python
3. Write Code: Use the built-in code editor with syntax highlighting
4. Add Input: Provide custom input for your program (optional)
5. Execute: Click run to compile and execute your code
6. View Results: See output, execution time, and memory usage

🔧 API Endpoints

Authentication

• POST /api/auth/register - User registration
• POST /api/auth/login - User login
• POST /api/auth/logout - User logout

Code Execution

• POST /api/code/execute - Submit code for execution
• GET /api/code/result/:id - Get execution results

🌐 Supported Languages

• C++ - Fast execution for competitive programming
• Java - Object-oriented programming with JVM
• Python - Simple syntax, perfect for algorithms
• JavaScript (Node.js) - Modern web development language

🤝 Contributing

1. Fork the repository
2. Create your feature branch (git checkout -b feature/AmazingFeature)
3. Commit your changes (git commit -m 'Add some AmazingFeature')
4. Push to the branch (git push origin feature/AmazingFeature)
5. Open a Pull Request

📝 License

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

👨‍💻 Author

Rohit Rana

• Email: [email protected]
• GitHub: @rohittrana
• LinkedIn: Rohit Rana

🙏 Acknowledgments

• Judge0 for providing the code execution API
• React community for the amazing frontend framework
• Open source contributors who make projects like this possible

---

⭐ Star this repo if you found it helpful!# LeetLab 🚀

A modern online coding platform that allows users to write, compile, and execute code in multiple programming languages with real-time feedback.

🌟 Features

• Multi-language Support: Write and execute code in Java, C++, JavaScript, and Python
• Real-time Code Execution: Powered by Judge0 API for fast and secure code compilation
• User Authentication: Custom-built login/signup system with secure session management
• Clean UI: Modern, responsive interface built with React
• Code Editor: Syntax highlighting and auto-completion for better coding experience
• Test Cases: Run your code against custom input/output test cases
• Results Dashboard: View execution time, memory usage, and output results

🛠️ Tech Stack

Frontend:

• React.js
• HTML5/CSS3
• JavaScript (ES6+)
• Responsive Design

Backend:

• Node.js/Express.js (or your backend tech)
• RESTful APIs
• JSON Web Tokens (JWT) for authentication
• bcrypt for password hashing

External APIs:

• Judge0 API for code compilation and execution

Database:

• MongoDB/PostgreSQL (specify your choice)

📁 Project Structure

leetlab/
├── frontend/           # React application
│   ├── src/
│   │   ├── components/
│   │   ├── pages/
│   │   ├── utils/
│   │   └── App.js
│   ├── public/
│   └── package.json
├── backend/            # Server application
│   ├── controllers/
│   ├── models/
│   ├── routes/
│   ├── middleware/
│   └── server.js
└── README.md

🚀 Getting Started

Prerequisites

• Node.js (v14 or higher)
• npm or yarn
• Judge0 API key (get it from Judge0)

Installation

1. Clone the repository

   git clone https://github.com/rohittrana/leetlab.git
   cd leetlab

2. Setup Backend

   cd backend
   npm install

   Create a .env file in the backend folder:

   PORT=5000
   MONGODB_URI=your_mongodb_connection_string
   JWT_SECRET=your_jwt_secret_key
   JUDGE0_API_KEY=your_judge0_api_key
   JUDGE0_HOST=judge0-ce.p.rapidapi.com

3. Setup Frontend

   cd ../frontend
   npm install

4. Start the Application

   Start backend server:

   cd backend
   npm start

   Start frontend (in new terminal):

   cd frontend
   npm start

5. Access the Application

   • Frontend: http://localhost:3000
   • Backend API: http://localhost:5000

🎯 How to Use

1. Sign Up/Login: Create an account or login with existing credentials
2. Choose Language: Select from Java, C++, JavaScript, or Python
3. Write Code: Use the built-in code editor with syntax highlighting
4. Add Input: Provide custom input for your program (optional)
5. Execute: Click run to compile and execute your code
6. View Results: See output, execution time, and memory usage

🔧 API Endpoints

Authentication

• POST /api/auth/register - User registration
• POST /api/auth/login - User login
• POST /api/auth/logout - User logout

Code Execution

• POST /api/code/execute - Submit code for execution
• GET /api/code/result/:id - Get execution results

🌐 Supported Languages

• C++ - Fast execution for competitive programming
• Java - Object-oriented programming with JVM
• Python - Simple syntax, perfect for algorithms
• JavaScript (Node.js) - Modern web development language

🤝 Contributing

1. Fork the repository
2. Create your feature branch (git checkout -b feature/AmazingFeature)
3. Commit your changes (git commit -m 'Add some AmazingFeature')
4. Push to the branch (git push origin feature/AmazingFeature)
5. Open a Pull Request

📝 License

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

👨‍💻 Author

Rohit Rana

• Email: [email protected]
• GitHub: @rohittrana
• LinkedIn: Rohit Rana

🙏 Acknowledgments

• Judge0 for providing the code execution API
• React community for the amazing frontend framework
• Open source contributors who make projects like this possible

---

⭐ Star this repo if you found it helpful!