What I'm trying to do:

In this project you will redo Programming Project 8 from Chapter 11 using a linked list instead of an array. As noted there, this is a linked list of double items. This fact may imply changes in some of the member functions. The members are as follows: a default constructor; a member function named add_item to add a double to the list; a test for a full list that is a Boolean-valued function named full( ); and a friend function overloading the insertion operator <<.

Here's the actual question:

8. Define a class called List that can hold a list of values of type double. Model your class definition after the class TemperatureList given in Display 11.10, but your class List will make no reference to temperatures when it outputs values. The values may represent any sort of data items as long as they are of type double. Include the additional features specified in Self-Test Exercises 21 and 22. Change the member function names so that they do not refer to temperature. Add a member function called get_last that takes no arguments and returns the last item on the list. The member function get_last does not change the list, and it should not be called if the list is empty. Add another member function called delete_last that deletes the last element on the list. The member function delete_last is a void function. Note that when the last element is deleted, the member variable size must be adjusted. If delete_last is called with an empty list as the calling object, the function call has no effect. Design a program to thoroughly test your definition for the class List.