Problem Statement

Overview

Build a bank system to create and manage user accounts, simulate deposits, withdrawals, interest accrual, and overdraft penalties.

Goals

• Support multiple account types with different rules
• Simulate real-world banking logic like minimum balance and interest
• Track user actions securely

Suggested Classes

• BankAccount: account_number, owner, balance, deposit(), withdraw()
• SavingsAccount(BankAccount): interest_rate, apply_interest()
• CheckingAccount(BankAccount): minimum_balance, penalty
• User: name, password, accounts[]

Features

• Create new accounts (checking/savings)
• Deposit money to account
• Withdraw money (with rules):
  • Checking: maintain minimum balance or pay penalty
  • Savings: limit to 3 withdrawals/month
• Apply interest monthly for savings
• Show account summary

OOP Concepts

• Inheritance: SavingsAccount and CheckingAccount from BankAccount
• Encapsulation: Balance, account actions hidden inside methods
• Polymorphism: Overridden withdraw() method in each subclass

Optional Extensions

• Password protection (simple CLI input masking)
• Transaction history with timestamp
• Monthly bank statement generation