🚀 DSA Sheet - Apna College | AI-Powered Learning Platform

The world's first AI-powered DSA practice platform with 373+ real problems, smart learning algorithms, and production-ready features.

🌟 What Makes This Special?

🤖 AI-Powered Features

• AI Mock Interviews - Real company-style technical interviews
• AI Problem Discussion - Get instant help on any coding problem
• AI Test Generator - Personalized tests based on your skill level
• Smart Code Review - AI analyzes your approach and suggests improvements

⏱️ Advanced Timer System

• Database-synced timer that never loses your progress
• Problem-specific time tracking with analytics
• Auto-stop on problem completion
• Performance insights and improvement suggestions

🧠 Scientific Learning

• Spaced Repetition Algorithm - Based on forgetting curve research
• Problems automatically scheduled for optimal retention
• Difficulty-based review intervals
• Progress optimization with minimal effort

📚 15+ Premium Sheets

• Apna College (373 problems) ✅
• Striver A2Z (455 problems) ✅
• Love Babbar (450 problems) ✅
• Blind 75 (75 problems) ✅
• NeetCode 150 (150 problems) ✅
• System Design (70 topics) ✅
• CP Sheets (500+ problems) ✅

Tech Stack:

Frontend: React 18 Vite Tailwind CSS Context API for state management

Backend: Node.js Express.js MongoDB with Mongoose JWT Authentication Google OAuth 2.0 Bcrypt for password hashing

Getting Started:

Prerequisites: Node.js (v16 or higher) MongoDB Google OAuth credentials

Installation:

1. Clone the repository

# Clone the project from GitHub
git clone https://github.com/shivamshrma09/ApnaCollegeDSASheet.git

# Navigate to project directory
cd ApnaCollegeDSASheet

2. Install dependencies

# Install root dependencies (if any)
npm install

# Install backend dependencies
cd Backend
npm install

# Install frontend dependencies
cd ../frontend
npm install

3. Environment Setup

Backend Environment (.env in Backend directory):

# Database Configuration
MONGO_URI=mongodb://localhost:27017/dsa-sheet
# or use MongoDB Atlas: mongodb+srv://username:password@cluster.mongodb.net/dsa-sheet

# JWT Secret Key
JWT_SECRET=your-super-secret-jwt-key-here

# Google OAuth Configuration
GOOGLE_CLIENT_ID=your-google-client-id
GOOGLE_CLIENT_SECRET=your-google-client-secret

# Server Configuration
PORT=5000
NODE_ENV=development

# Frontend URL (for CORS)
FRONTEND_URL=http://localhost:3000

Frontend Environment (.env in frontend directory):

# Backend API URL
VITE_API_URL=http://localhost:5000/api

# Google OAuth Client ID (same as backend)
VITE_GOOGLE_CLIENT_ID=your-google-client-id

# App Configuration
VITE_APP_NAME=DSA Sheet - Apna College
VITE_APP_VERSION=1.0.0

How to get Google OAuth credentials:

• Go to Google Cloud Console
• Create a new project or select existing one
• Enable Google+ API
• Go to Credentials → Create Credentials → OAuth 2.0 Client IDs
• Add authorized redirect URIs:
  • http://localhost:3000 (for frontend)
  • http://localhost:5000/auth/google/callback (for backend)

4. Database Setup

# Option 1: Local MongoDB
# Install MongoDB locally and start the service
# MongoDB will run on mongodb://localhost:27017

# Option 2: MongoDB Atlas (Recommended)
# 1. Create account at https://www.mongodb.com/atlas
# 2. Create a new cluster
# 3. Get connection string and add to MONGO_URI in .env

5. Start the application

# Terminal 1: Start Backend Server
cd Backend
npm start
# Backend will run on http://localhost:5000

# Terminal 2: Start Frontend Development Server
cd frontend
npm run dev
# Frontend will run on http://localhost:3000

Verification Steps:

• Backend: Visit http://localhost:5000/api/health (should return server status)
• Frontend: Visit http://localhost:3000 (should load the application)
• Database: Check MongoDB connection in backend console logs

Project Structure:

Backend/ - Node.js backend controllers/ - Route controllers models/ - MongoDB models routes/ - API routes middleware/ - Custom middleware config/ - Database configuration frontend/ - React frontend src/ components/ contexts/ data/ hooks/ public/ README.md

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 open source and available under the MIT License.