Hi,
you should really consider to convert the 12 digit string to a 64bit
struct
like
typedef struct tagBigNum
{
UInt32 hi; // first 6 digits
UInt32 lo ; // last 6 digits
}
BigNum ;
Holding an array of 12 byte strings would not be very effective (#items x
12bytes. You could also sort the BigNum array and use SysBinarySearch instead
of hashing. Anyway a good method for hashing numbers is to take the middle
bits of the square, eg. (x*x >> 4) & 0xFFFF. You could do this for both hi
and lo and combine it to a long.
On Sunday 29 May 2005 17:11, Katie A. (Moor) Siek wrote:
> I'm trying to hash a string. It is a string of numbers, but the number
> is 12 digits long - too big for a Int32.
>
> Thanks,
> Katie
>
> On May 29, 2005, at 1:39 AM, Logan Shaw wrote:
> > Katie A. (Moor) Siek wrote:
> >> Also, does anyone know a good hash function that works on Palms?
> >
> > Surely that would depend on what kind data you're trying to hash...
> >
> > Strings? Floating point numbers? Prime numbers? RGB values?
> > Pointers?
> >
> > - Logan
> >
> > --
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>
> *~~*~~*~~*~~*~~*~~*~~*~~*~~*~~*~~*~~*~~*~~*~~*~~*~~*~~*~~*~~*
> Katie A. (Moor) Siek
> PhD Candidate (812) 856-2107
> Indiana University [EMAIL PROTECTED]
> Computer Science Department http://www.cs.indiana.edu/~ksiek
> *~~*~~*~~*~~*~~*~~*~~*~~*~~*~~*~~*~~*~~*~~*~~*~~*~~*~~*~~*~~*
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