Bike Rental System

A University OOP Project!

Description

The general struture of system is smth like this:

|__Class (main)
    |__Class (Bike)
            |__Class (ElectricBike)
            |__Class (RoadBike)
    |__Class (User)

details of Class(main):

`User_menu()` function which should contain the following:
    1. Available Bikes
    2. Rented Bikes
    3. Return Bike
    4. Rent a Bike!
    5. List of Bikes
    6. My rent history
    7. Exit

`Admin_menu()` function should contain following:
    1. Add Bike(s)
    2. Add new Admin
    3. Add new User
    4. List of Users
    5. List of Bikes
    6. Load Data
    7. Exit

details of Class(Bike):

it should contain many properties and methods like: `IsRented` or `SerialNumber` and etc.

details of Class(ElectricBike):

it should contain many properties and methods like: `IsRented` or `SerialNumber` or `Charged` and 
etc.

details of Class(RoadBike):

it should contain many properties and methods like: `IsRented` or `SerialNumber` and 
etc.

Class(User) details:

it should completely implemented and contain `username`, `RentalList`, etc...

NOTE! maximum 3 Bikes can rent every single person.