Hello Codeforces community!

I am glad to announce that HackerRank 101 Hack 31st edition will be held on 19th Nov 2015 at 16:30 UTC. You can sign up for the contest here. Though what's priceless is solving interesting problems and the thrill of competition, prizes make the competition fierce. Top 10 performers will get a HackerRank T-shirt.

Problems have been set by shangjingbo and tested by wanbo. The contest will consist of 5 problems with variable scoring distribution. We have tried our best to prepare a nice problem set. Hopefully everyone will enjoy. Also, you'll be able to enjoy the detailed editorials written by the setter.

If anyone are interested in sharing their knowledge, you can comment in this post or send message to me directly. We eagerly need bunch of good problems.

Good luck and have fun!

update 1: The editorial has been added, please upsolving the harder problems which you haven't solved in the contest.

update 2: The contest has been unrated because of the bad/misleading statement for the 3rd problem. We are apologize for that. We will show you more high quality contests in the future.