In article <3D52E88C.16537.23333D2@localhost>,
"Markus Laire" <[EMAIL PROTECTED]> writes:
> You need to regex last zeroes AND remove extra numbers in the
> beginning keeping only last 6 (or so) numbers.
Interesting enough you need 6 when counting up and 5 when counting down
>
> I can't resist mentioning my other solution which doesn't compute n!
> at all, but just uses kind-of 3D lookup-table to find the result.
> It's fast but unfortunately code is far too long :(
>
> $z=pop;sub g{vec"\x10\xd7\xa9\x98b\xef",pop,2}
> print$z<2||(1+g$z%25)*(1,3,2,4)[g 24-$z/25%25]*6*(1+g$z/625)%10,$/
>
> Explanation would be somewhat longer, but if anyone wants I can write
> it.
>
> Has anyone else tried lookup instead of computing n!. I'd like to
> know shortest possible solution for this sub-problem also.
>
For a general direct method, see
http://www.mathpages.com/home/kmath489.htm
