// Account class (Base class)
class Account {
 private int accountNumber;
 private double balance;
 public Account(int accountNumber) {
 this.accountNumber = accountNumber;
 this.balance = 0.0;
 }
 public int getAccountNumber() {
 return accountNumber;
 }
 public double getBalance() {
 return balance;
 }
 public void deposit(double amount) {
 balance += amount;
 System.out.println("Deposited: $" + amount);
 }
 public void withdraw(double amount) {
 if (amount <= balance) {
 balance -= amount;
 System.out.println("Withdrawn: $" + amount);
 } else {
 System.out.println("Insufficient balance");
 }
 }
}
// Subclasses of Account
class SavingsAccount extends Account {
 // Additional features specific to savings account
 public SavingsAccount(int accountNumber) {
 super(accountNumber);
 }
}
class CheckingAccount extends Account {
 // Additional features specific to checking account
 public CheckingAccount(int accountNumber) {
 super(accountNumber);
 }
}
// Customer class
class Customer {
 private String name;
 private Account account;
 public Customer(String name, Account account) {
 this.name = name;
 this.account = account;
 }
 public void deposit(double amount) {
 account.deposit(amount);
 }
 public void withdraw(double amount) {
 account.withdraw(amount);
 }
 public double checkBalance() {
 return account.getBalance();
 }
}
// Employee class
class Employee {
 private String name;
 public Employee(String name) {
 this.name = name;
 }
 public void processTransaction(Customer customer, double amount,
String type) {
 if (type.equalsIgnoreCase("Deposit")) {
 customer.deposit(amount);
 } else if (type.equalsIgnoreCase("Withdraw")) {
 customer.withdraw(amount);
 } else {
 System.out.println("Invalid transaction type");
 }
 }
}
// Main class for testing
public class BankingApplication {
 public static void main(String[] args) {
 // Create accounts for customers
 SavingsAccount savingsAccount = new SavingsAccount(1001);
 CheckingAccount checkingAccount = new CheckingAccount(2001);
 // Create customers and link accounts
 Customer customer1 = new Customer("Alice", savingsAccount);
 Customer customer2 = new Customer("Bob", checkingAccount);
 // Create bank employees
 Employee employee1 = new Employee("Eve");
 // Employee processing transactions for customers
 employee1.processTransaction(customer1, 1000, "Deposit");
 employee1.processTransaction(customer2, 500, "Withdraw");
 // Checking customer balances after transactions
 System.out.println("Customer 1 Balance: $" +
customer1.checkBalance());
 System.out.println("Customer 2 Balance: $" +
customer2.checkBalance());
 }
}