mirror of
https://git.tartarus.org/simon/putty.git
synced 2025-04-12 00:28:06 -05:00
072d3c665a
I'm about to want to solve quartics mod a prime, which means I'll need to be able to take cube roots mod p as well as square roots. This commit introduces a more general class which can take rth roots for any prime r, and moreover, it can do it in a general cyclic group. (You have to tell it the group's order and give it some primitives for doing arithmetic, plus a way of iterating over the group elements that it can use to look for a non-rth-power and roots of unity.) That system makes it nicely easy to test, because you can give it a cyclic group represented as the integers under _addition_, and then you obviously know what all the right answers are. So I've also added a unit test system checking that.