Write a C$++$ program that will implement the following tasks to help students understand how to use friend functions. Make sure to use appropriate variable types and display the results clearly.

Class Definition:

a$)$ Define a class named "Rectangle" with the following private members:

length $($double$)$: to store the length of the rectangle.

width $($double$)$: to store the width of the rectangle.

b$)$ Declare a constructor for the "Rectangle" class that takes parameters to initialize the length and width.

c$)$ Declare a friend function named "calculateArea" that takes a constant reference to a "Rectangle" object as a parameter.

d$)$ Inside the "calculateArea" function, calculate and return the area of the rectangle using the length and width members of the object.

Object Creation:

a$)$ Inside the main function, create an object of the "Rectangle" class.

b$)$ Prompt the user to enter values for the length and width of the rectangle.

c$)$ Use the provided input to initialize the object's members.

d$)$ Display the details of the rectangle object.

e$)$ Call the "calculateArea" function and pass the rectangle object as an argument.

f$)$ Display the calculated area of the rectangle.

Friend Function Implementation:

a$)$ Implement the "calculateArea" friend function outside the class definition.

b$)$ The friend function should have access to the private members of the "Rectangle" class.

c$)$ Calculate and return the area of the rectangle using the length and width members of the object passed as a parameter.

Additional Functionality:

a$)$ Declare a friend function named "compareRectangles" that takes two constant references to "Rectangle" objects as parameters.

b$)$ Inside the "compareRectangles" function, compare the areas of the two rectangles.

c$)$ Display a suitable message indicating which rectangle has a larger area or if both rectangles have the same area.

d$)$ Call the "compareRectangles" function from the main function and pass two rectangle objects as arguments.