Hello,I doubt that this guy is cheating spoj.pl/users/macedonian_boy/2
what makes me dubious when I notice that this guy is submitting solution too fast which is virtually impossible for any coder to solve in that time gap. Take a look at this : spoj.pl/status/macedonian_boy/signedlist/4
I request the concerning problem setter/administrator to look into his solutions and take appropriate action if found guilty.