debug print statement instead of removing it 
in case our modification fails and we need to debug again. Then we added
a guardian statement that checks to see if we have zero words, and if so, 
we use <tt>continue</tt> to skip to the next line in the file.<br />
<br />
We can think of the two <tt>continue</tt> statements as helping us refine
the set of lines which are "interesting" to us and which we want 
to process some more. A line which has no words is "uninteresting" to 
us so we skip to the next line.