🏦 Bank Account Management System (C++)

This project is a C++ console-based application that simulates a simple banking system.
It demonstrates the use of Object-Oriented Programming (OOP) principles including abstraction, inheritance, polymorphism, exception handling, and dynamic memory management.

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📖 Overview

The system allows users to create and manage savings accounts. It provides operations such as deposits, withdrawals, applying interest, and displaying account details.
All accounts are stored dynamically using std::vector, ensuring scalability and flexibility.

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🎮 Features

• Account Management
  • Create a new savings account with a unique account number
  • Display account details by account number
  • Display all existing accounts
• Transactions
  • Deposit money (validates positive input)
  • Withdraw money (checks sufficient balance)
• Interest
  • Apply fixed interest (5%) to all savings accounts
• Menu-Driven Interface
  • User-friendly console menu with structured options

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🏗️ Class Design

Account (Abstract Base Class)

• Attributes
  • int accountNumber
  • std::string holderName
  • float balance
• Pure Virtual Methods
  • deposit(float)
  • withdraw(float)
  • displayDetails()
  • applyInterest()

SavingsAccount (Derived Class)

• Inherits from Account
• Additional Attribute
  • float interestRate = 0.05
• Overrides
  • Implements deposit and withdraw with exception handling
  • Defines applyInterest() to increase balance by 5%
  • Custom displayDetails()

Data Management

• Uses std::vector<Account*> accounts;
• Enables storing multiple accounts dynamically with polymorphism.

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⚙️ Implementation Highlights

• Polymorphism → base class pointers calling derived class methods
• Exception Handling → ensures robust input validation for deposits and withdrawals
• Validation Functions
  • checkIfAccountExists() → prevents duplicate accounts
  • checkIfAccountsEmpty() → prevents invalid operations when no accounts exist

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📂 Project Structure

bank-account-management-system-cpp/
│
├── src/
│   └── BankSystem.cpp              # Main source code
│
├── SystemDesign(UML-Style_Plan).pdf # System design diagram
│
└── README.md

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▶️ How to Run

Compile the program using g++:

g++ src/BankSystem.cpp -o BankSystem
./BankSystem

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📸 Sample Output

Welcome to the Bank Account Management System
---------------------------------------------
1 -> Main Menu
2 -> Exit

*********** Main Menu ***********
1 -> Create New Account
2 -> Deposit
3 -> Withdraw
4 -> Display Details By Account Number
5 -> Display All Accounts
6 -> Apply Interest (for savings)
0 -> Opening Menu

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🛠️ Technologies

• Language: C++ (C++11 standard and above)
• Data Structures: std::vector for dynamic storage
• Concepts Used: OOP (abstraction, inheritance, polymorphism), exception handling

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📑 Documentation

• SystemDesign(UML-Style_Plan).pdf → High-level system design diagram

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🚀 Future Improvements

• Support for multiple account types (e.g., CheckingAccount, BusinessAccount)
• File I/O for saving and loading accounts
• Extended interest rate configurations
• More advanced error handling and input validation

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📜 License

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