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Something that's often said in combination to what you said is to keep your functions short (like 7 code lines).

Most people will whine at that, but the fact is you can't hold more than 7 lines in your head anyway. And, like you said, your code should just be a sequence of very explicit functions:

adjustColor();
scalePicture();
cropPicture();
addWatermark();

and the same in each of those functions.

(These guys say 62, YMMV)

See also http://acm.uva.es/ and http://spoj.pl/

...one thing that is not of concern is input parsing. We had so much practice reading in any well-defined formats. The hard part is really finding the best algorithm that is asymptotically the best. Remember that your solution must compute not just a few sample questions. It will have to process 1000-1000000 test cases in under a few seconds and under certain memory limits. When you focus on the core algorithm and incorporate the scaffolding for input and into automation---you only need to focus on the algorithm and doing it correctly. The test cases the judges run during each submission test for all previously known 'base cases' and will ensure that any solution less than 100% perfect will fail. If you are interested in practicing ACM problems... please check out the Spanish ACM Archives. (http://acm.uva.es/ Pick a problem and submit it to the online judge and see how it is. The trick to a lot of these problems is the mathematics of the solution--not necessarily any 'computation'. Why compute something recursively, when there's a theorem that can provide the answer immediately? The problems are designed to capitalize on 'tricks' like this.

The contest has changed a lot over the years. I would agree that the tasks of many moons ago are quite simple algorithmically: on this year's contest I suspect you would have a great deal more trouble. For an example of recent World Finals problems, please see The live archive. I think you'll find them much more interesting.

For those who want to know more about this contest in the form of actually attempting ACM questions, then I suggest heading over to their problemset archive which not only has ACM stuff from the last 5 years but a large number of non-ACM programming problems in the same vein. You can sign up with them and have your solutions to their problems checked for correctness.

Since the website's a design massacre, to get to the ACM problems you need to click on the link marked THE CII ICPC LIVE ARCHIVE !!! in the news bar, or just click on that one right there.

For those who want to know more about this contest in the form of actually attempting ACM questions, then I suggest heading over to their problemset archive which not only has ACM stuff from the last 5 years but a large number of non-ACM programming problems in the same vein. You can sign up with them and have your solutions to their problems checked for correctness.

Since the website's a design massacre, to get to the ACM problems you need to click on the link marked THE CII ICPC LIVE ARCHIVE !!! in the news bar, or just click on that one right there.

Use sprintf(3), surely?

Good interview of Miguel de Icaza about Mono.

Notable reduction in the IKVM's size (thanks to Eclipse Java Compiler [jdtcore.jar]).

More about IKVM's weblog.

Good LiveCD Monoppix-v1.1.8.0!!!

;)

By + + + J.C. Pizarro + + + ATH OK.

The ACM puts up a lot of programming challenges and have an automatic judge system to determine if your solution is correct or not. They have hundreds of problems of varying difficulty:

http://acm.uva.es/

Programming Challenges is a nifty book by Steven Skiena and Miguel Revilla. It's a selection of problems from the Online-Judge problem set. There's a lot of nifty stuff in there - sorting, graph theory, number theory, etc.

Best of all, when folks solve the problems, they can submit their solutions online to see if they pass muster!

Well, if you're willing to limit yourself to C, C++, Java, or Pascal, you may want to have a look at some of the problems available at The Online Jodge. You can code them up and submit them to have them tested for speed and correctness.

Universidad de Valladolid has a large archive of programming problems. The online judge allows C, C++, Java, and Pascal.

http://acm.uva.es/problemset/

The ACM problem sets. I don't know when the current problems get added, but all the old ones, plus more, are on this site. You can write the program, then submit it to their online judge to see if it's correct.

Brute force usually doesn't work, so you need to know the right algorithm. It's tough, but it's fun!

Which year and competition (regional or final?) was that? Do you have a link to the problem set? Is that problem in the uva judge?

There are no prizes, the problems are not terribly hard (they are aimed at college-level participants), but you get geek points (whatever those are) and it's fun (in my opinion, at least).

There are no prizes, the problems are not terribly hard (they are aimed at college-level participants), but you get geek points (whatever those are) and it's fun (in my opinion, at least).

There are no prizes, the problems are not terribly hard (they are aimed at college-level participants), but you get geek points (whatever those are) and it's fun (in my opinion, at least).

There are no prizes, the problems are not terribly hard (they are aimed at college-level participants), but you get geek points (whatever those are) and it's fun (in my opinion, at least).

http://online-judge.uva.es/problemset/ //Jesper Miller

For the rest of us, there will be an on-line public competition hosted through the Valladolid site and run by the University of Waterloo. The next one is on the 19th (3 days away!), free, and everyone can register. Stock up on doritos and join in the fun!

I also do problems from the UVA ACM problemset, which are typically more difficult. However, they aren't realtime, so they don't get give you any competitve rush like topcoder.

The ACM Contest is similiar; it's linked at the bottom of the IPSC website. You have 5 hours to do 6-9 problems. Most are a real pain and brute force usually won't work... it needs to be time and memory efficient. But it's fun. Their website has a ton of problems, like 10,000+, and you can submit to there online judge... it always gives me something to do on Friday/Saturday nights.

you might want to have a look at AntiCrack which is a huge collection of tutorials cracking , reverse engineering, and programming. They also have a copy of the Old Fravia'Site, the new one being about searching).

There's a few games/challenges out there about reverse engineering, cracking, logic and programming. Give them a try if you wish (Arcanum is really nice):
AngularVision, Apotheosis, Arcanum, Aspect, Aspect2, C&CDisIncorporated, CyberArmy, Disavowed, Electrica, Escape, HackME, HackersGames, HackersLab, HackQuest, Hybrid, ICEFortress, Lamebulun, Mod-X, NetSplit, NGSEC'sSecurityGame, ProblemSetArchive, ReverserCourse, SlyFX, TheGame, and Try2hack.

have fun ;-)

Algorithm-based programming contests tend to become a matter of who can see the underlying problem - is it shortest path? is it combinatorics? - then modifying one of the algorithms in Sedgewick for the constraints.

The time pressure tends to discourage you from thinking up a nice, neat, elegant solution when a quick brute-force hack will run in the specified time.

I have the greatest respect for the kind of problems at the ACM contests - that problemset archive is cool! But contests like that tend to encourage bad coding style (it looks pretty the first time around, but then you start kludging it to make your output look like the test output) and lack of input checking (all inputs assumed correct).

Oh, well, it's really a personal thing I guess.

Algorithm-based programming contests tend to become a matter of who can see the underlying problem - is it shortest path? is it combinatorics? - then modifying one of the algorithms in Sedgewick for the constraints.

The time pressure tends to discourage you from thinking up a nice, neat, elegant solution when a quick brute-force hack will run in the specified time.

I have the greatest respect for the kind of problems at the ACM contests - that problemset archive is cool! But contests like that tend to encourage bad coding style (it looks pretty the first time around, but then you start kludging it to make your output look like the test output) and lack of input checking (all inputs assumed correct).

Oh, well, it's really a personal thing I guess.

Pointless experimentation? You admit it is an experiment. Voice-over-IP isn't something everyone uses often, and here is a non-profit low-cost effort to build a global network of linked repeaters using VoIP. Sounds interesting to me.

Yes using it isn't may not be exciting to use if you are using to using HF communications directly, but not everyone has HF privileges. It sounds quite interesting to build. It would be one of the easiest ways that an amateur with only VHF privileges can communicate world-wide, using a low-power handheld 2m or 70cm radio. Sounds like a neat experiment, and something that a new ham might find inspiring to work towards HF qualifications because of.

Using an Internet link does not always mean using a "phone line". If you checked out the site, you'd see part of their link in BC uses wireless ethernet. You could build a node that uses HF packet carring TCP/IP and VoIP. Nothing is to prevent that, and it would be compatible with other wired repeaters.

A lot of your message sounds like what was said about repeaters back in the 70s or any new digital mode from RTTY to PSK31, AMSAT, and likely about SSB[1] versus AM.

1. single sideband, suppressed carrier, uses less bandwidth than AM

I competed on the University of Alberta team in the '98 and '99 finals. Congratulations to this year's team!

Here's a few quick hints:

• Have a firm grasp of standard algorithms (shortest path, max flow, etc.) Bring printouts.
• An excellent source for sample problems may be found at http://acm.fi.uva.es/.
• Practice both individually and as a team. Decide in advance how you will share the single terminal. If you can't find a bug within a few minutes, print out your code and let someone else have the workstation.

Good luck!

- Adam