Processing genome using Flex and Bison

Is it possible? Has anyone ever tried?

I'm looking at a bacteria right now, just downloaded 2.8MB of ATCG madness. Wondering if DNA is a regular language.

XKCD Time Strip

I want to download all the pictures featured on the time strip. I think that the image name is cryptic using Skein. But, there is an easy way: people are uploading the drawings on the XKCD Wikia. So I installed wget on Windows8. Tried this without success. Any ideas?

 for ($i=50; $i -le 55; $i++)  
 {wget --wait=1 -r -P . -A png "http://xkcd-time.wikia.com/wiki/File:Time$i.png"}  

The png images downloaded are corrupted.