postmortem of 2010 winner : https://www.a1k0n.net/2010/03/04/google-ai-postmortem.html
The tourney will be run on csmarlboro.org, so whatever language or libraries you want to use, make sure it's installed there.
testing & debugging :
You can use a my-move/their-move tree to look ahead for the best move. The algorithm to search for the best move is minmax.
The flood fill algorithm can measure how big a room is : https://en.wikipedia.org/wiki/Flood_fill .
The A* algorithm can find a best path to a specific place : https://en.wikipedia.org/wiki/A*_search_algorithm
Don't think for too long :