Any tips/tricks for short Java sourcecode?

[joeycozza]

I am really curious how some users are able to submit such small sourcecode answers in Java. I was wondering what tips/tricks/rules you use when trying to write a program with the fewest characters possible. Something I realized recently is that you don't have to put "public" in front of the class name. Of course using 1 letter variable names is good, but what else? Any ideas?

[jimmyjack]

I'm not an expert for c(++) programming, so I won't comment on your code too much. Generally you should look for constraints and suitable data types in

problem statement
problem comments
forum (use the search engine)

Here I'm not sure if you used long long data type. The comments show some tricky test cases.
Good luck.
Daft