Jolly Challenge #15! Lets participate :)

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10	pajenegod	145

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: