Google Code Jam 2013 is underway!

The qualification round for Google Code Jam 2013 has started, and will run for about 20 more hours (until 4am on Sunday Moscow time). If you haven't already, you should take part. I'm involved with preparing problems for this competition, and hope you will like them :)

Note that the time when you submit your solution doesn't matter in the qualification round, so those who started before you have no unfair advantage. You just have to submit before the round ends.

Also note that you must not discuss the problems and solutions with others before the round ends. Online programming competitions are based in a large part on the honesty of their participants, so don't spoil it for everyone!