Hello everyone!

I'm solving the problem called "castle" from IOI'94. I solved it about 1.5 hour, and when I checked my solution with sample test and it was correct, I was so happy that finished debugging the code=) But when I submitted it I had signal #9. Please, tell me, what can it be?

By the way, here is my [code]("http://ideone.com/e.js/lqRaTb" type="text/javascript").