Yes, compiled C code is much faster than perl for this task, I'm afraid. I have a C version that runs
over 100 times faster than the perl, so it completes in a fraction of a second. I used
GMP, which provides a wide
variety of functions and has optimized assembly code for many platforms.
Pari seems to be a bit faster, but the documentation is way over my head.
I see Math::BigIntFast is available in PPM form. Someone who was feeling ambitious could probably make that work, but the rational number support would have to be written.