Hackerrank organized another programming contests from 23.10.2015 17:30 CEST to 25.10.2015 CET called Ad Infinitum 13 - Math Programming Contest, which I participaded in.
It was my 12th contest at Hackerrank and I think I was quite successfull. I was able to solve 3 challenges and earned full points:
Game with coins
The Deletion Game
I partially solved
Multiply! challenge and earned 6/60 points.
My final result 276/1220.
All solutions are available on my GitHub.