Lecture Overview

• I continued talking about pointers, references, structs, and arrays which I did not finish last time. Again these topics are covered in Chapter 3 of Thinking in C++.

C++ Array Stacks

arraystack.cpp contains an implementation of ArrayStacks. A few points:

• C++ already has an implementation of the list ADT called vector and it is described at the end of Chpater 2 of TICPP. All actual C++ code which needs a list ADT should use vectors! I am showing this implementation of ArrayStacks just as an example, you should never use this code.
• The ArrayStack is specialized to only store strings, because again this is just for demonstration purposes. In C++ it is possible to create containers that can hold any type (in fact vector does so), but we haven't learned that yet and at the moment I just want to focus on implementing ArrayStacks in C++.
• The methods use an assert to make sure the index passed to get, set, and add are within range. This will crash the program with a message if the assert is invalid (try it out!). This is fine for this simple demonstration, but in a real program you would want to use exceptions so that the program does not just crash.

Exercises

No specific exercises today, just complete the exercises from last time on pointers.