Path: utzoo!attcan!uunet!lll-winken!lll-tis!ames!mailrus!uflorida!novavax!proxftl!bill From: bill@proxftl.UUCP (T. William Wells) Newsgroups: comp.lang.c Subject: Re: hash algorithm Keywords: hash Message-ID: <609@proxftl.UUCP> Date: 19 Aug 88 04:00:02 GMT References: <654@novavax.UUCP> Reply-To: bill@proxftl.UUCP (T. William Wells) Organization: Proximity Technology, Ft. Lauderdale Lines: 14 Summary: Expires: Sender: Followup-To: Distribution: In article <654@novavax.UUCP> raab@novavax.UUCP (Moshe Raab) writes: : could anyone recommend a hashing algorithm to store a list of 10 : digit phone numbers (area code plus 7 digits). : It should have little or no overflow and no collisions (as few as : possible). The list will contain more than one area code but : about 1000 numbers per area code (ie not a totasly random sample : but one which has a relatively common prefix) : thank you very much. You might want to try a hash trie (sic). The Programming Pearls column in the June 1986 Communications of the ACM describes one way to do this. I have not tried this so I can give you no estimates on the space needed to do it, but access to a hash trie is very fast though perhaps not as fast as a very sparse hash table.