This is a quick demo that shows how to use CSAPP functions in your
C programs.

First, use the provided Makefile to compile the program. Then, run
the program:

    $ make
    $ ./main

The Makefile has the required options/flags to let the compiler know
where the CSAPP functions/code lives. 

In main.c, I make sure to include the csapp.h header file.

- Eric

