From: Mark Space <markspace@sbc.global.net>
Subject: Re: find words that contains some specific letters
Date: Sat, 06 Jun 2009 10:11:32 -0700
Date: 2009-06-06T10:11:32-07:00 [thread overview]
Message-ID: <frxWl.34710$ZP4.32560@nlpi067.nbdc.sbc.com> (raw)
In-Reply-To: <nospam-B6C8E0.12131906062009@news.aioe.org>
John B. Matthews wrote:
>> For example the Character class.
>
> I think all of the primitive wrappers (except Double) have trivially
> perfect integer hashes, as they wrap distinct values. Patricia was
> perhaps referring to algorithms of the kind discussed here:
>
> <http://en.wikipedia.org/wiki/Perfect_hash_function>
I remember in school we implemented a minimal perfect hash function on a
given set of keys: the keywords in the Pascal language. We were given
the parameters of the algorithm: use the length of the keyword, the
first character and the last character only.
The concept was obviously to show how a fast look-up could be done when
implementing a compiler, but the hash function itself was interesting at
the time.
next prev parent reply other threads:[~2009-06-06 17:11 UTC|newest]
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2009-06-06 16:13 ` find words that contains some specific letters John B. Matthews
2009-06-06 16:22 ` Patricia Shanahan
2009-06-06 20:42 ` Giovanni Azua
2009-06-06 23:43 ` Giovanni Azua
2009-06-06 17:11 ` Mark Space [this message]
2009-06-06 18:23 ` Lew
2009-06-06 23:58 ` Tom Anderson
2009-06-07 19:30 ` John B. Matthews
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