After a small alteration, by totally ignoring the sample code and creating a .html file in the /ads/ folder, I created what we see on this forum; an ad after each post. It looks like this:

However, it looks like Google Adsense is not publishing more than three ads on the same page. I guess, this is really good... can't be too much, people are easily annoyed by all the commercials they are exposed to everywhere.