Hi to everybody from sunny Petrozavodsk!

Today me and my brother sdya prepared a few interesting problems for you. Because of very tight schedule in Petrozavodsk training camp, that includes rafting and watching anime all night long, we didn't have time to write long problem statements. So enjoy unambiguous short statements and you are welcome to invent some legends for them on your own.

Good luck and have fun!

Contest is over! Congratulations to winners!

Division 1:

Division 2:

Editorial.

Contest is over! Congratulations to winners!

Division 1:

Division 2:

Editorial.

rown. "The "lock" icon disappeared.

http://www.codechef.com/SEPT11/problems/SHORT

For the case 18 4.

Why is 6 not a solution, it does not divide any of 14,15,16,17 . Or did I miss something miniscule.

Thanks.

Usually authors write special program - checker, that checks your answer, using input and jury output for this test. Moreover, sometimes checker program can be much more difficult then solution.

Did I miss something or it is a mistake in author's solution?

OOOX

XOOO

OOXO

X - spots, where all the spiders ends up, you can reach an X from any square.

(1,3)

(2,1)

(3,4)

(4,2)

(numbering starts from1 )

Thanks Seyaua and sdya for problems :)

Any one else didn't see the n.m<=40 constraint in C DIV-1?

UPD: Yeah, baby, give me more minuses, people never like truth =)nandm(1 ≤n·m≤ 40) — the board sizes.1.first rotate the grid such that smaller side remains at top, which is of length <= 6. (sqrt(40)).

2.then try all possible subsets (2^6).

3.any particular state is given by settled spiders in curr. row and prev row. and the curr row number.

4.Easy if you have solved similar problems previously.

the timer should be started as a problem is opened or at least when someone enters the contest area!

But seriously, I don't get what isn't fair - that's the rules of this competition. It's like arriving late to a rock star concert and complaining afterwards that he started before you arrive. The advantages and disadvantages of particular format (CodeForces/ACM/TopCoder/IOI etc.) is another topic.

Sorry if I misunderstood your post.

It's always priceless to see these kind of comments.

## ?detaR tI sI