How I Enjoyed the Rock Paper Azure Competition

In mid-December, I saw an ad on StackOverflow.com and was immediately intrigued. “Rock, Paper, Azure!” was a contest run by Microsoft wherein programmers design bots to compete in a modified game of Rock, Paper, Scissors. The bots had to be hosted in Microsoft’s cloud computing platform, Azure, so you can easily see Microsoft’s motivation to give away some small prizes to influence developers into trying and (hopefully) adopting Azure.

Although I had plenty of things to keep me busy leading up to Christmas, the Rock, Paper, Azure marketing worked on me. I figured I could take 1 or 2 hours out of my time and write the best algorithm I could in that time. Besides, I would be entered into the grand-prize contest drawing just for competing with even the most simple of bots.

I was immediately reminded of a school project from an early Computer Science course at Ohio State. The contest back then pitted “bug bots” from teams of students in the course against each other. Each team started out with a handful of bugs on a large virtual checker board. A bug could “convert” another student’s bug by facing it and issuing the “bite” command. The bitten bug would then become a member of the “biting” bug’s army. The game continues until one team has converted all bugs. If I remember correctly, there were only a few possible commands:

• “Detect” if an object (like a wall or another bug) was in front of it
• “Move” forward 1 square
• “Rotate” left or right
• “Bite”

It may have evolved since then, but our bot did surprisingly well back then despite a very simple algorithm:

1. If something in front, turn left, bite.
2. Else, move forward, bite.
3. Repeat Step 1.

I’ve often wondered what additional strategy I would write into my bot if given another opportunity in such a competition. Rock, Paper, Azure was the challenge I was looking for.

Microsoft’s version of “roshambo” came with a few twists, such as the introduction of the dynamite and water balloon moves. Check out all the details and rules here. I liked that it was a simple game but with competition against other developers’ bots came many options for creative strategy. Additionally, I was extremely impressed with how simple it was to build the basic bot.

Game Rule Highlights:

• Bots compete each other throwing one of Rock, Paper, Scissors, Dynamite, or Water Balloon
• Normal rules apply except that the Dynamite beats everything but Water Balloon and Water Balloon loses to everything but Dynamite
• Each bot only gets to use Dynamite 100 times
• First bot to win 1000 times wins the entire match
• Ties carry over, so the next round could be worth more than 1 win (similar to “Skins” in golf)

It took me some iteration to come up with my eventual strategy, which turned out to be admittedly mediocre (98^th place out of 162). I realized that my bot can keep track of the history of moves that it has made as well as the moves of my opponent. My plan was to try and detect if my opponent was falling into a sort of pattern. I was especially concerned about the end of the round when we both would be desperately throwing dynamite to close out the match. As you can see, my strategy only had a small amount of success.

Nonetheless, I thoroughly enjoyed my time creating and deploying my bot. I encourage Microsoft to search for more clever ways to get developers interested in learning and using their development platforms. In this contest, I got to expand my mind, learn more about Azure, and I even got a free t-shirt. Here’s to the next competition!