Bank Management System

A simple C++ console-based Bank Management System featuring the following functionality:

1. Banks – Create and manage Bank objects, each with a unique ID and set of customers.
2. Customers – Add and manage Customer objects (name, ID, age).
3. Accounts – Create Checking or Saving accounts for each customer.
4. Transactions – Perform deposits, withdrawals, and transfers.
5. Interest – Apply interest (for Saving accounts).
6. File Output – Write all bank/customer/account/transaction data to a file.

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Project Structure

• include/ holds the header files for each class (Bank, Customer, BankAccount, etc.).
• src/ holds the .cpp files implementing these classes and the main entry point (main.cpp).
• Makefile compiles and links everything into an executable.
• bank_info.txt (generated at runtime) contains a summary of all banks, customers, accounts, and transactions.

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Features

• Add Bank – Creates a new Bank with a user-provided name, assigned a random ID.
• Add Customer – Associates a new Customer with an existing Bank.
• Add Account – Creates a Checking or Saving account for a chosen Customer.
• Add Transaction – Performs a Deposit, Withdraw, or Transfer on a chosen Account.
• View All ... – View all banks, customers in a bank, accounts of a customer, or transactions of an account.
• Search – Look up banks, customers, accounts, or transactions by ID.
• Apply Interest – Applies a global interest rate to all SavingAccount's.
• Write To File – Outputs all data to bank_info.txt in a hierarchical format.

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Building

1. Ensure you have a C++20 compiler (e.g., g++ 11 or later).

2. Navigate to the project root directory.

3. Run make all to compile:

   make all

   This should create the executable (e.g. main.exe on Windows or ./main on Mac/Linux).

4. Optionally, run make clean to remove object files and the executable.

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Running the Application

1. Build the project as described above.

2. Run the resulting executable:

   # On Linux / macOS:
   ./main
   
   # On Windows:
   main.exe

3. You will see a menu of numbered options. Enter the number of the action you want to perform (e.g., “1” for Add Bank, “2” for Add Customer, etc.).

4. Regularly “Write To File” (option 14) so you can easily look up the assigned IDs. You must enter those IDs to add or view items in future steps.

5. Exit the application by selecting option 15.

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Usage Example

1. Add Bank

   • Provide a bank name, e.g. “MyBank.” The system will display the new bank’s ID (or you can later see it in bank_info.txt).

2. Add Customer

   • Enter the bank ID you just created. Supply the customer’s first/last name and age. The system will generate a customer ID.

3. Write To File

   • After adding the customer, select “Write To File” to record the new IDs in bank_info.txt. This file shows you the bank’s ID, the customer’s ID, etc.

4. Add Account

   • Enter the same bank ID again, and then the customer ID from step 3.
   • Choose Checking or Saving, and specify the initial balance. An account ID is automatically assigned.

5. Write To File again if you like, so you can see the new account’s ID and reference it later.

6. Add Transaction

   • Enter the bank ID, the customer ID, and the account ID.
   • Choose a transaction type (DEPOSIT, WITHDRAW, TRANSFER) and enter the amount.
   • If successful, the system will show you the updated balance or apply fees (CheckingAccount only).

7. View All Accounts or View All Transactions to verify changes. Or Write To File once more to record everything.

8. Exit

   • Once done, use the “Exit” option (menu item 15).

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License

This project is provided as-is, without warranty or guarantee. You are free to modify or extend it for your needs.

Enjoy using the Bank Management System!