Discussion @ 1388. Photo @ Timus Online Judge

To ADMIN, Sample Incorrect?

Posted by Safe Bird 25 Oct 2005 17:11

I think for sample2, the correct output should be 2.

Am I right? Or please inform me if I misunderstood the description. Thanx.

Re: To ADMIN, Sample Incorrect?

Posted by Kit (Vologda SPU) 25 Oct 2005 18:06

It seems, we can take lines y = 1 and x + y = -1. What do you think of it?

Can you explain it in details?(haven't understood yet)

Posted by Safe Bird 26 Oct 2005 18:39

hmm.....i cannot understand either

Posted by Mithril 26 Oct 2005 18:59

please .

Re: Can you explain it in details?(haven't understood yet)

Posted by Kit (Vologda SPU) 26 Oct 2005 20:34

Trees on the upper side (y > 0) are centrally projected on a line y = 1. Trees on the lower side are centrally projected on a line x + y = -1 (or x + y = -4, if you wish). After scaling both films will be same.

But I can't imagine how it can be solved :(((. Any ideas?

You meant that the film is something like a line with infinity length?

Posted by Safe Bird 26 Oct 2005 21:23

Yes, the film is an infinite line (-)

Posted by Vladimir Yakovlev (USU) 27 Oct 2005 11:58

So the intersections(+)

Posted by Safe Bird 28 Oct 2005 22:14

So the intersections of
1.film (infinity line)
2.the line connecting (0,0) and some points
are what that would be projected.

Edited by author 02.11.2005 19:30

Discussion of Problem 1388. Photo