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Subject: Re: Hash Table Collisions

Author: KarinsDad

Date: 12:10:25 04/13/00

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On April 13, 2000 at 12:19:45, Tom Kerrigan wrote:

[snip]
>
>Now I'm confused. :)  Are you talking about doing a search A and during that
>search, it overwrites a hash entry made by the same search (A)?
>
>-Tom


This is how I'm looking at it. We do search A with counter 23. We find a node in
the current search in the tree. It has counter 22 (it was entered last search)
and is the same position. Fine. We move on in the search. Later on, we find a
node that has counter 23, but is not the same position. We are fairly confident
that we placed it here in search A. We have to decide whether to keep it or
overwrite it.

If we keep it, then hopefully the node that we did not place into the hash will
not be in the descendents of final move chosen by search A.

If we overwrite it, than hopefully the node that we overwrote will not be in the
descendents of final move chosen by search A.

Therefore, it could be a crap shoot as to whether a given descendent node is in
the hash.

Does this make sense?

KarinsDad :)



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