Infinite-precision arithmetic

[Cubist at aol.com]

sez xbury.cs at clearstream.com:
>Very nice!
   Thanks!

>That's the easy part though ;)
   [nods] Don't I know it!

>Divisions is where it gets harder...
   And square roots... and powers... and DIV and MOD... and...
   I've already come up with an infinite-precision algorithm for 
multiplication which looks promising; I haven't coded it up yet, however, so I am not 
entirely certain how well it will work out "in real life". In pseudocode:

InfPreMult N1, N2
  put 0 into Rezult
  Put N1 into Fred
  Repeat until N2 = 0
    If N1 is odd then add Adder to Rezult
    Add Fred to Fred
    put N1 div 2 into N1
  end repeat
End of algorithm

   Naturally, there's also the option of splitting N1 and N2 up into 
7-character chunks, doing all the multiplies for the relevant chunk-pairs, and 
combining the results of said multiplies. That looks like it'd be a pain to code, so 
I am going to try the other algorithm first. Depending on how fast it is, I 
may or may not want to give "7-char chunks" a try as well.

>...and using arrays may be much more efficient than using strings or 
numbers...
>But items could work well too but wouldn't it be slower?
   I've never touched arrays before. I shall have to see if arrays make a 
difference, speed-wise. Every millisecond -- heck, every *micro*second -- counts 
in this sort of thing.