Hello. Not a long time ago I moved to US (more particulaty to PA). So, I figured out everything with school, and now I'm curious about cp here. I know about codechef, atcoder, google jam and others, but I want to know more about specifically US stuff (the only thing I know is usaco). So, I have two following questions:

1) What local cp contests are worth participating in?

2) I want to start doing math, so I have same question about math contests.

Thank you in advance.