In the qualification round, all the participants were given a chance to work on 2 problems in 1 hour. The participants can log in into the arena any time in a day from March 20 to 21, 2006 but once they opened one of the problem, they only have 1 hour to finish the 2 problems. See the complete rules for the qualification round.
Around 14,000 participants were randomly distributed to a room and each room will be assigned one of the 5 problem sets (each set contains 2 problems: 250pt and 1000pt). Here is the 5 problem sets:
There was so many cheaters during this qualification round since the qualification round is open for the whole day, and it gave an opportuinity for cheaters to cheat (I don't want to discuss how to cheat).