Those are the problems I loathe the most, where the real problem is figuring out how to parse the input into something more workable. Once its parsed its ezpz.
Are you solving all puzzles? I find usually that the parsing isn't my problem, but some of the puzzles puzzle me (ha, couldn't resist), because they expect some kind of graph knowledge or some mathematical trick or so. Last year got stuck at day 17 for example. Usually some learning in it then, but parsing, while possibly annoying day after day, wasn't usually what stopped me from completing puzzles.
