Schönhage–Strassen's algorithm for multiplying large numbers?

Question

Algorithms

I read the English Wikipedia , there are a lot of details, but questions still remain. For example, how to effectively choose the parameters N, etc. Maybe somewhere there is a compact implementation that is easy to read and does not drag large libraries with it? The C language would be perfect. If I don’t find it, it looks like I’ll have to gut GMP ...

Answer 1

www.ginac.de/CLN/
Can be assembled without GMP