This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
I think forandboth this and b in the go() method refer to the same object. Therefore this can be replaced by b which makes it a bit more readable.
In the case of go() is called from within go(). Thereforeis done twice resulting in being 7. The answer is 2 7 then.