even more progress

I'm on exercise 27 now in LPTHW. I think I've spent a total of four or five hours on it. It really helps already being familiar with C since I don't have any issues comprehending the "advanced" stuff so far (functions, return values, taking arguments, importing functions from other files). I'm still weak on some of the formatting like %d and %s and %r in the print statements, but basically it's numbers, strings, and a different way of formatting string statements.