I still don't see the memorization part. The last time I touched quicksort was at uni, three years ago, I still understand how it works (choose a pivot, partition the rest according to the elements' relation to the pivot, then quicksort the partitions), and I'm pretty sure I'd be able to implement it right now. Maybe not in C, but in Ruby, absolutely.

Understanding is the hard part, the implementation should be the automatic part. I mean, we're programmers, right? We know how to shuffle arrays around and return values from functions.