My implementation of simple ruby Binary Reverse puzzle from Spotify

I stumbled upon Spotify puzzle page while checking out their jobs page. I love Spotify and working for them would be cool. But they only want submision based on Python, C++ or Java.

I wrote one in ruby still. Not much of an implementation but I did it as proper as I could.

Any comment on how I can improve the code is appreciate.

P/S: I don't know the etiquette here at Hacker News. Especially with regards to posting submission like this. Tell me if I violate any kind of code of conduct or anything.