Hi Codeforces,

I am taking this opportunity to announce HackerRank Hour-Rank 15, a 60 minute contest where the fastest coder wins!. The contest will be held on 16:30 UTC Saturday, 3rd December, 2016. You can sing up for the contest here. As you can probably guess, i am author of this contest and i promise you all to deliver an interesting problem set with something for all. I really want to thank danilka.pro for testing all the problems and helping me to come up with nice problem set. My special thanks to Shafaet for bringing me back to my problem setting and helping me to work hard for this contest.