== Project Overview ==

The provided Java code is a simple car rental system. It includes classes to represent cars, customers, and rental transactions. The system allows users to add cars and customers, rent and return cars, and view available cars. The main class initiates the system and provides a user-friendly menu for interactions, such as renting a car, returning a car, viewing available cars, and exiting the system. The code incorporates error handling for user inputs and includes comments for better understanding.

Car Class

The Car class represents a vehicle with attributes such as car ID, brand, model, base price per day, and availability. It has methods to calculate rental prices, mark the car as rented, and mark the car as available.

Customer Class

The Customer class represents a customer with attributes like name and a unique customer ID.

Rental Class

The Rental class encapsulates information about a car rental, including the rented car, customer, and the rental duration.

CarRentalSystem Class

The CarRentalSystem class manages the car rental system, storing lists of cars, customers, and rental transactions. It provides methods to add cars and customers, rent and return cars, and a menu for user interaction.

Main Class

The Main class contains the main method, creating an instance of CarRentalSystem and initiating the menu for user interaction. It adds some sample cars to the system