🌐 Smart Connect – User Network Path Finder

🧩 Overview

Smart Connect is a Java-based console application that combines graph algorithms, sorting algorithms, and basic user management to simulate a small city-based social connection system.

It allows users to:

• Register and log in
• View other user accounts
• Sort accounts by age (using Merge Sort)
• Find the shortest path and all possible paths between their location and another user's location (using Dijkstra’s Algorithm and Depth-First Search)

This project was developed as part of a 5th semester university Algorithm course to demonstrate the application of graph traversal, shortest path algorithms, and sorting techniques in an interactive Java program.

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🚀 Features

✅ User registration and login system
✅ Displays user profiles with location-based connections
✅ Sorts users by age using Merge Sort
✅ Finds shortest path (Dijkstra’s Algorithm) between two locations
✅ Lists all possible paths (DFS Traversal)
✅ Simulates real-world distances between city areas
✅ Interactive console interface

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⚙️ Technologies Used

• Language: Java
• Algorithmic Concepts:
  • Dijkstra’s Algorithm (Shortest Path)
  • Depth-First Search (DFS)
  • Merge Sort
• Data Structures: Arrays, Lists, Graph (Adjacency List)

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🧱 Project Structure

SmartConnect/
  ├── Main.java 
  └── README.md

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🧭 Locations Map

The graph connects five major areas as nodes:

Location Index	Area Name
0	Mohakhali
1	Mirpur
2	Cantornment
3	Ghulshan
4	Dhanmondi

Each area is connected to others with different distances (weights in kilometers).
For example:

Mohakhali -> Mirpur (3 km)
Mirpur -> Cantornment (1 km)
Ghulshan -> Dhanmondi (4 km)

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🧠 Algorithms Implemented

🧩 1. Merge Sort

Used to sort all existing user accounts by age.

mergeSort(users, 0, users.length - 1);

🚗 2. Dijkstra’s Algorithm

Finds the shortest path between the logged-in user’s location and another user’s location.

int[] shortestPaths = dijkstra(userLocation);

🌐 3. Depth-First Search (DFS)

Generates all possible paths between two users’ locations for exploration.

dfs(userLocation, destination, visited, currentPath, allPaths);

💻 How to Run

▶️ Compile

javac Main.java

▶️ Execute

java Main

The program will prompt:

1. To create an account
2. To log in
3. To input your personal and location details
4. To view or sort user profiles
5. To find paths and distances between locations

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🧮 Sample Flow

Welcome! Let's create your account.
Enter username: asif
Enter password: ****

=== Login ===
Enter username: asif
Enter password: ****
Login Successful!

Choose an account to view:
1. Alice
2. Eve
3. Bob
4. David
5. Charlie
6. Sort accounts by age

When a user is selected, the program shows:

• Account details
• Shortest path between locations (via Dijkstra)
• All possible paths (via DFS)
• Option to view contact details

🧰 Example Output

Shortest path from user to chosen account: 4 km

All possible paths:
Path: Mohakhali -> Ghulshan -> Dhanmondi (Distance: 9 km)
Path: Mohakhali -> Mirpur -> Cantornment -> Dhanmondi (Distance: 12 km)

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🪄 Future Enhancements

• Add a GUI (Swing)
• Store users in a file or database
• Visualize paths using a graph visualization library
• Allow dynamic addition/removal of nodes (locations)

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📝Author

Anowarul Asif
📧 Reach Me Here
🌐 Portfolio | 🔗 LinkedIn | 🐙 GitHub

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⭐ Contribute

Contributions are welcome! Follow these steps:

1. Fork the repository
2. Create a new branch: git checkout -b feature-name
3. Commit your changes: git commit -m "Add feature"
4. Push to your fork: git push origin feature-name
5. Open a Pull Request

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🛡️ License

This project is licensed under the MIT License — feel free to use and modify it.