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Re: [computer-go] Re: Sharing Secrets



Frank de Groot wrote:

No, that will work just fine for an editor.
The "issue" is about hash collision avoidance.
When you start thinking ahead (or when you have a huge pattern database),
you will need millions of hashes and you'll get collisions even with 64-bit
hashing if you have not "taken care of the issue :)".

I have never heard of a hashing class in any programming language, neither
of any literary source that satisfactorily solves this "issue" best. The
very rare sources that hint at a really good solution are incomplete and in
fact even lead astray.
Most programmers conveniently ignore the issue. And they might as well.
Even if they store 2^24 positions in a hashtable, and do a search of 2^24
positions, the collision probability is at most 2^(24+24-64) = 1/65536,
which can be considered negligable.

They will start thinking about the issue in 10 years when they store 2^30
positions and search 2^30, bumping the collision probability to 1/16.
At that time, moving to 96-bit hashes seems the easy solution...

regards,
-John
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