Challenges By Blarney in Blarney's Diary Thu Jul 31, 2014 at 10:53:57 PM EST Tags: software problem, ogg frog, super debugging, basic income, MOOC, challenge (all tags)
	I have to admit that, for all the discussion of 'challenges' around here, I hadn't really tried any. Now I have. The point of this site CodeEval seems to be that you can complete challenges to win the ability to apply for jobs, and get a good ranking to brag about on your LinkedIn. So now I know what 'challenges' really are - they remind me of the homework that my friends who actually took computer science courses always had to do. I really liked this problem, credited to our overlords at Google. It took me most of a day to figure it out because I'm not that smart, I scored 97/100 ranking points for speed/memory, but I bet you Kurons could do it much quicker.

I did a few other 'challenges' but I liked this one because there was more to it than looking up an algorithm in Knuth or on Wikipedia and typing it in. It's kind of spooky to think about - the problem involves finding which of 3N-1 expressions satisfy certain criteria, and if you want it to work well for large N you have to do it without actually evaluating each expression - very holistic in feel. Stuff I learned while doing it: Seriously FUCK octal it sucks. Why does '011' still evaluate to 9 in so many languages? It's 2014, there is no PDP11, there is no Lisp Machine, and hopefully anyone who even tries to invent a new CPU with an 18-bit word length will be taken outside and shot. Why do we have to preserve some greybeard's stupid in-joke? I don't know much about regexes, but I ended up writing a regex to remove leading zeros from numbers inside arithmetic expressions. I better not lose it as I may need it again someday. It was still less of a pain than rewriting 'eval' would have been. I shouldn't have skipped number theory class so often. Thankfully I still remember some of it. You can totally do all the math for this problem in Z210. Once I noticed that I could do the math in Z210, I realized that I should. Because that is how people who write problems think - they want you to use the 'trick' they taught you, just as I described in my farce The Cookie Problem I am not a genius but I am pretty good at psyching out test problems. Yes, there is a way to divide-and-conquer so that you don't have to eval every possible expression. (Un)surprisingly, doing things in Z210 actually helped. It's pretty complicated, at least more than, say, qsort. Sadly, to actually get a high site ranking so IMFs will employ me, I need to do lots of these problems, not just the ones that look fun. Like, I would need to grind through FizzBuzz and stuff to get a high score. Which would show to a prospective employer that I love to do lots of boring repetitive work even without getting paid - so why they'd paid me to do more of it, I haven't a clue. Given the mercenary Friedmanesque hot flat crowded low-wage global slum ethic behind it, I'm glad I got a little fun out of it. It was fun watching my submission do a 15-digit string just like THAT. Boom. It did take me all day to get there. How about you guys?

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Seeking employment? No I am a superdebugger and i will always have a job 0% The Creators of Jorbs will bless me if I vote Tea Party and buy guns 50% I would eat a turd for $1,000,000. 50% Who are we kidding? I'd eat a turd for, like, $100. I've had worse jobs. 0% Votes: 2 Results | Other Polls

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