How to {win|do well in} a
Programming Contest

Written by Jeffrey Sharkey

Well, by now you've probably Googled "how to win a programming contest." If you haven't, then go do that for awhile and come back later. ;) jk

Everyone seems to have different answers and strategies. I've only competed in two contests, so I'm no expert. But there were a few things that stuck out in my mind.

Team

Hopefully you were told that you'll be on a team. (Yay!) If you think you don't need a team, go build a pyramid and come back when you're finished. lol

Spend a lot of time with your team; working out practice problems, eating pizza, memorizing library functions, etc. Find a few evenings and meet in a classroom with chalk and a projector. You don't need to pound out fully coded solutions, but at least walk through the problem solving process together.

Try finding a team of people you've [successfully] worked with before. If that doesn't work out, contest teams are a great way to make new friends. Get over any personality clashes ASAP. ;)

Skills

Swapping out several coders on the same computer isn't a great idea. Find someone who can type fast, and make them your resident coder. They don't need to have the best coding skills, but they have to type accurately and fast.

Two people should code together, watching and talking with the fast typer. That way you'll all know the code, and can help with debugging advice. Let the coder finish mundane output formatting while you start working on the next problem.

Don't waste time writing full pseudo-code on paper. Jot down general ideas like:

split string on periods and count sentences
for each sentence, split on spaces to count words

Only include loop details if important, otherwise keep them as action context like "for each" above. Lightweight pseudo-code will keep your team fast.

For the actual programming, know (yes, in order of importance):

• String manipulation. You should be best friends with split and substring. Regular expressions may help in a pinch, so learn the basics like replacing using capture groups () and quantities ?,+,*. Only use regex when it's faster than coding and when you won't have to pull out a reference book to make it work.
• Comment and indent lazily. Only write comments for broad sections of code (if even that), and don't worry about indenting too much. Yes, indent for loops and conditionals, but not for methods or classes (using vertical whitespace is faster). Keep names short and concise, but reserve one-letter variables for loops. par, sent, word are perfect, and prevent spelling mistakes.
• Classes can help! You'll mostly write horrid procedural code, but if you've got a problem that screams OOP, then code it that way. Checking an input matrix for 90, 180, 270 rotations? Make a class that can rotate 90, then use clones and perform multiple rotations to solve. Don't go overboard by writing an entire abstract framework, but watch for smart applications.
• File IO. Everyone always uses text mode, so forget binary. Think about using hard-coded test strings to make debugging faster, and switch to input files later. Also, think of an easy way to dump output to console (for fast debugging), but quickly switch to file output when finished. (Java lets you cast your choice of System.out or a FileOutputStream to a generic OutputStream.) Never forget to switch over to file IO in the end.
• Number idiosyncrasies. Know what your language supports. Example: the Java byte supports 256 values, but is signed (-127 to 128). Also look at formatting options (NumberFormatter in Java), because your output will probably pump out a lot of numbers.

Finally, put special emphasis on practice problems specific to your event. Most contests are fairly uniform, but always know your contest better.

Attitude

Go read up on sportsmanship at Wikipedia. Being a card-carrying geek doesn't exempt you. ;) Never blame your teammates, never throw keyboards, and always have fun.

Oh, and hey, let me know how your team did! I was the coder on the UMD team that won DigiKey DKC3 in 2005, and placed first at our location in the 2005 ACM Regional competition. Go UMD! :)