Announcements (Search)

by bbi5291 on Nov 06, 2011 - 3:51:58 am UTC
  • (3/0)
This box ( now runs an IRC server.
You can also use the web client at, if you are lame.

Multiple submissions of identical code

by bbi5291 on Oct 24, 2011 - 4:52:07 am UTC
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A reminder not to do this. It clutters up the submissions page. Don't complain if you find that I end up deleting all your solutions to a particular problem in an effort to delete all the duplicates.

Migrated to Xen server

by bbi5291 on Oct 11, 2011 - 10:58:35 pm UTC
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The Judge has been moved to a server with dedicated resources. Performance should now be better on all fronts (although some programs now take longer to execute; I'm looking into why this is).
This is costing me $28/month, so donations would be appreciated.
If you notice any issues, just mention them here.

Who wants problem setter and contest setter support?

by bbi5291 on Jun 24, 2011 - 11:00:03 pm UTC
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I've decided that there's no immediate need to refactor the contest system as I had initially planned. I used to think the inefficiency of the database logic caused the poor performance of the site, and that it was fast sometimes because of caching. The actual truth is that all the slowness is due to occasional extremely high network latency, so nothing I do can guarantee that the site never takes 10 seconds to load (except moving to a dedicated server, which is actually too expensive).

I don't see any major issues with the Judge and I think it has all the piecen an online judge would be expected to have, with one exception --- support for non-admin problem setters and contest setters (as in SPOJ, which I consider the "industry standard", although we did have a comment system before they did, I think).

How many [non-admins] would like to become problem setters and contest setters, and how often do you see yourself adding problems?

After I add this functionality (if there is sufficient interest), I plan to basically stop active development on the Judge (barring some major breakthrough such as a significant expansion of the user base).

Migration complete

by bbi5291 on Jun 18, 2011 - 8:33:50 am UTC
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The Judge has been moved to a new server.

If you notice anything strange over the next few weeks, let me know.

Note that this machine is slower than the previous one by a factor of about 1.3, so runtimes will differ accordingly.

Loss of data

by bbi5291 on Jun 06, 2011 - 5:56:56 pm UTC
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Comment ratings from January onward have somehow been deleted. Sorry for the inconvenience.


by bbi5291 on Mar 27, 2011 - 3:44:30 am UTC
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Recently, due to a performance bug, the Judge spent more than an hour trying to judge one submission. I have made some changes to prevent this from happening in the future, but if I have made any mistakes then some programs may be judged incorrect even when they are correct. If this happens then please make a note of it here and I'll fix it as soon as possible.

Session Expiry

by admin on Mar 03, 2011 - 5:27:34 pm UTC
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Sessions should expire if user is inactive for 2-3 hours.
Joyce neglected to log off of Admin yesterday and when I opened my account on the same computer today, it was already logged in as Admin.

Ratings updated

by bbi5291 on Feb 23, 2011 - 5:37:41 am UTC
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Mock CCC Analyses

by SourSpinach on Feb 22, 2011 - 9:39:10 pm UTC
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Now that the contest is over, it's a great opportunity to learn how to solve these types of problems - they represent the various things that can quite possible come up on the CCC.
The analyses and test data can be found here: here