Problem J - World Finals 2005

[shahriar_manzoor]

Yes u missed it. But it is not a big deal as the contestants r to be focused in the prize giving ceremony. Judges were on stage for a brief period as the link below shows:
http://icpc.baylor.edu/dmt/view_image.asp?i=16776&size=reg.

It is odd to post someones own image but I don't think anyone will be able to answer this question but me as I struggled a lot to find this image.

[fernando]

Any hint or idea about solving problem B without computing Voronoi diagram?