Richard J. Cichelli
Abstract
A method is presented for computing machine independent, minimal perfect hash functions of the form: hash value ← key length + the associated value of the key's first character + the associated value of the key's last character. Such functions allow single probe retrieval from minimally sized tables of identifier lists. Application areas include table lookup for reserved words in compilers and filtering high frequency words in natural language processing. Functions for Pascal's reserved words, Pascal's predefined identifiers, frequently occurring English words, and month abbreviations are presented as examples.
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Digital Library
- 2 Sheil, B.A. Median split trees: A fast lookup technique for frequently occurring keys. Comm. ACM 21, 11 (Nov. 1978), 947-958. Google ScholarDigital Library
- 3 Sprugnoli, R. Perfect hashing functions: A single probe retrieving method for static sets. Comm. ACM 20, I l (Nov. 1977), 841-850. Google ScholarDigital Library
Index Terms
- Minimal perfect hash functions made simple
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