**Elimination round is over!**

Thank you all for participating in the elimination round of Bayan Contest. The final results are available. We had more than three thousand registered users for the contest on Codeforces and one third of them were able to solve at least one problem. In the meantime 1100 Iranian contestants participated in our local contest and half of them solved a problem.

We tried hard to prepare a challenging-yet-fun problemset.

The problem "241G - Challenging Balloons" was inspired from a real story! The problem described in the story was used in CEOI 2011 (Task Balloons), and the provided algorithm was the author's solution during that contest — which got the full mark indeed.

According to statistics, "241D - Numbers" was the hardest problem. A tricky approach to the solution is to ignore large inputs and solve the problem for small values of *n*. You may observe that it is possible to find the demanded subset within a small part of input. During the contest, no one solved all the problems but there was at least one successful attempt for each of them.

We hope you enjoyed it all!

As stated before, Top 100 contestants will be receiving T-shirts. So, update your contact information and T-Shirt size in your Codeforces profile. We'll start sending the prizes as soon as possible.

#### And the winners...

The winners will receive invitation letters — to the on-site event — soon. If you are one of them make sure your contact information is up-to-date.

Congratulations to all the participants, specially the winners. See you in Tehran!

Good Luck

I've got 70 (here) points using the solution from the problem about ballons and your solution is not the same like the author's one published here.

Did they change the solution?

This author is not that author! The author of problem G got 100 points on CEOI using that algorithm. :)

It simply means the test data was not strong enough. Therefore a naive + greedy solution managed to get 100.

I guess test data is ok since the solution described in problem G won't pass.

To make the problem simpler, we had to change the algorithm a bit. But the idea was the same.

Oh, now everything is clear. It is something I was talking about in the very beginning.

Are you going to publish the editorial for the whole problemset?

Has anyone received invitation letter?

<mode name = "math.logic"> don't know <mode>

I don't think so

I am wondering how many people of the participants who rank among 11 to 20 would go to Tehran with expense of flight on their own.......and so lucky the 10th!

I'll bet for 0.

Hahaha..I guess you got it!And I really miss VK Cup(I'd say it was really well organized and the participants got really well rewarded..regardless of the T-shirt that my friend still haven't received)

Can you please at least specify exact dates of onsite event? I need to plan my time in advance

The exact date is February 15th. It is going to be held in Sharif University of Technology.

How to solve E? I see solutions do something similar to the Belmman Ford algorithm over the edges that are on a path from 1 to n, but I don't get why it should work?

Try to google "system of difference constraints".

Have anyone received a t-shirt? I still haven't.