Programming Books

I already have several books on hand that I own the cover how to program and how to use various programming languages. And that's cool.

What I'm looking for is a book that has good challenges in it for a developing programmer. Program challenges like sorting strings, doing math, using ports and memory, etc.

Can someone point me in some direction here?

does Jew math dance
it was mind-expanding! F u if u dont agrrree. :)