📚 Digital Due Records - Store Management System 🧾

🚀 Overview

Digital Due Records is a digital ledger system, developed in C, designed to replace traditional "Katha" (account book) systems used in Indian stores. This project streamlines the management of customer dues, generates bills, and maintains well-organized records with minimal effort. It aims to provide an efficient, modern solution for store owners to track and manage financial data securely.

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🌟 Key Features

🔐 Dual Access System

• Customer Portal: Securely view dues and transaction history.
• Admin Portal: Password-protected, offering store management capabilities.

📝 Customer Record Management

• Add, update, and delete customer records.
• Automatic bill generation with real-time due calculations.
• Automatically clear records when dues are settled.

🔍 Advanced Search and Sort

• Search by:
  • Customer name (case-insensitive).
  • Transaction date.
• Sort records by:
  • Customer name.
  • Due amount.
  • Transaction date.
• Flexible sorting options with linked list implementation, supporting both temporary and permanent sorting.

🛡️ Enhanced Security

• Password-protected admin access with recovery options.
• Security questions for account recovery.
• Limited login attempts for added protection.

💼 Store Management

• Customizable store details (name, address, contact).
• Professional bill generation and record management.
• User-friendly interface, requiring no technical knowledge.

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🛠️ Technical Details

Data Structures:

• Structures:
  • Customer: Stores customer details and transactions.
  • SecurityQuestions: Manages admin credentials securely.
  • StoreDetails: Stores essential store-related information.
• Linked Lists:
  • Used for dynamic record management.
  • Enables efficient sorting and memory management.

File Handling:

• Binary files for secure and persistent data storage.
• Text files for bill generation.
• Temporary files for intermediate operations.

Memory Management:

• Dynamic memory allocation using malloc().
• Proper deallocation using free() to prevent memory leaks.

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🧑‍💻 Skills Demonstrated

💡 Programming Concepts:

• Structured Programming.
• Advanced Data Structures (Linked Lists).
• File I/O operations.
• Memory Management.
• Robust Input Validation.

🛠️ Software Engineering:

• Modular Design: Easily maintainable and extendable codebase.
• User Interface Design: Clear, simple, and intuitive interface.
• Secure Authentication: Strong user authentication with password and security questions.
• Error Handling: Comprehensive error handling and debugging.

🧠 Problem Solving:

• Efficient data search and sort algorithms.
• User authentication and security management.
• Real-time due calculations for customers.

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⚙️ Project Setup

⚡ Quick Start:

1. Download and run the executable.
2. The first-time setup will guide you through:
   • Admin password creation.
   • Security question configuration.
   • Store details input.
3. Ready to use immediately after setup.

🏁 First-Time Setup Process:

1. System creates necessary files:
   • DueCustomers.txt: Stores customer records.
   • password.bin: Manages admin credentials.
   • store.txt: Stores store details.
2. System guides you through:
   • Password creation (minimum 8 characters).
   • Security question setup (4 questions).
3. Validates all inputs to ensure smooth operation.

🛠️ Daily Usage:

1. Launch the program.
2. Choose between Customer or Admin access.
3. Perform actions like adding transactions, viewing records, and generating bills.

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💻 System Requirements:

• C Compiler (GCC preferred).
• Windows OS or compatible environment.
• Minimum 512MB RAM.
• 10MB free disk space.
• No additional software or internet required.

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🚀 Open to Contributions:

This project is open for collaborations and improvements. Feel free to fork, modify, and enhance the system for your needs or contribute back to the repository. Together, we can make it even better!