[computer-go] Adjacent Strings/Chains

[Phil G]

How does everyone keep track of adjacent strings/chains? For each string, I keep a count of the # stones for each adjacent string (include empty strings). Strings are also removed then they don't have any adjacent neighbors (i.e., it's been captured, or it's was part of a merged string that isn't used anymore). It's was fast and easy to implement. However, it's a bit slow. I was wondering if someone has a better method.
 
- Phil