Looking for data structures for long integer

Hello everyone,


I need to represent long integer (longer than 8 bytes, which can not be represented by C/C++ built-in types). I need to implement add (+) and multiply (*) operations on such data structures efficiently. Does anyone have ideas of how to implement it or any reference materials?


thanks in advance,
George

If you search the forums, there is a popular big number library out there. I'll try to get a link for you.

EDIT: GMP