Hello great codeforces community! We are glad to invite you to participate in Jolly Challenge #15.

The contest will be held on Friday 15 January 2016 from 13:00 UTC to 15:30 UTC (check it at your timezone here: http://www.timeanddate.com/worldclock/fixedtime.html?msg=Jolly+Challenge+%2315&iso=20160115T13&p1=1440&ah=2&am=30 )

This contest consist of 5 or 6 ACM-ICPC style problems sorted by expected dificulty, all problems are prepared by me ( tjandra ), tested by SandyKarunia, rickychandra, and setiadialvin.

You can register the contest here: https://jollybeeoj.com/contest/

Good Luck & Have Fun! :D

---Additional information---

Each problem has images or ASCII art to help you understanding problem description and demonstrate how the output in some sample case is produced. rickychandra also help fixing some typo and grammar error if any. So we do our best to make the problem as clearly as possible. Even it's nearly impossible for this contest to have unclear statement, if there are some part that is still unclear, you can ask clarificarion in contest menu.

All problem (should) have interesting story, there are 3 people in this contest problem story:

• Tjandra: Always investigating for information if any problem occur

• Satria: Smart person, usually make amazing experiment

• Gunawan: Don't want to lose to Satria, but usually his action make some trouble

Problem difficulty will vary in wide range, the easiest problem is expected to be easily solvable by green CF coder, the hardest problem is expected to be challenging for violet CF coder. I also plan to add 1 more problem (6th problem), if I success (most likely I will) that problem is expected to be very hard for violet CF user, hahaha!

---About Myself---

If you wonder, my name is Tjandra, I start programming since late 2011, I become SPOJ problemsetter at May 2012 (you can check my SPOJ profile here: http://www.spoj.com/users/tjandra/ ), and I become SPOJ Editorial Board at December 2014 so my job at SPOJ is mainly checking problem quality (edit unclear problem or delete bad problem).

By the way, you can 'taste' some of my past problem here:

• My sample problem on SPOJ: http://www.spoj.com/problems/TJANDRAS/

• My sample problem on Jollybee: https://jollybeeoj.com/problem/view/197

Looking forward to see you at the top of scoreboard,

Register the contest here: https://jollybeeoj.com/contest/

When I check country rank table on: http://codeforces.net/ratings/country/Indonesia

I found some green user, but his rating is above 1500, here is the screenshoot:

Then I click that user (visit his profile page), his rating is below 1500 after participating codeforces round #216, but in rank table it still showing 1500+ rating.

After that I check the global rank table on: http://codeforces.net/ratings/page/53

And not only Indonesia, every(?) participant round #216 which have rating update from Expert to Specialist doesn't update in the rank table properly, here is more screenshoot:

Let me know if it's only happen to me (not codeforces bug). I've checked by browsing on both my smartphone and my laptop (both have different internet source), but the result is same, showing green user but with rating above 1500 on rank table.

Sorry if there're some typo on my post or the picture/screenshoot is too large for you (especially for those who browsing via smartphone or similar devices).