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Fast Scalable Construction of (Minimal Perfect Hash) Functions [PDF]
, 2016 Recent advances in random linear systems on finite fields have paved the way for the construction of constant-time data structures representing static functions and minimal perfect hash functions using less space with respect to existing techniques.
Marco Genuzio +2 more
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Finding minimal perfect hash functions [PDF]
ACM SIGCSE Bulletin, 1986 A heuristic is given for finding minimal perfect hash functions without extensive searching. The procedure is to construct a set of graph (or hypergraph) models for the dictionary, then choose one of the models for use in constructing the minimal perfect hashing function.
Gary Haggard, Kevin Karplus
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Hash and Displace: Efficient Evaluation of Minimal Perfect Hash Functions
BRICS Report Series, 1999 A new way of constructing (minimal) perfect hash functions is described. The<br />technique considerably reduces the overhead associated with resolving buckets in two-level hashing schemes. Evaluating a hash function requires just one multiplication and a few additions apart from primitive bit operations.
Rasmus Pagh
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Perfect hashing functions [PDF]
Communications of the ACM, 1977 A refinement of hashing which allows retrieval of an item in a static table with a single probe is considered. Given a set I of identifiers, two methods are presented for building, in a mechanical way, perfect hashing functions, i.e. functions transforming the elements of I into unique addresses.
Renzo Sprugnoli
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Engineering Minimal k-Perfect Hash Functions
Given a set $S$ of $n$ keys, a $k$-perfect hash function (kPHF) is a data structure that maps the keys to the first m integers, where each output integer can be hit by at most k input keys. When $m = ⌈n/k⌉$, the resulting function is called a minimal k-perfect hash function (MkPHF).
Hermann Stefan +4 more
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A Linear Time Algorithm for Finding Minimal Perfect Hash Functions [PDF]
The Computer Journal, 1993 Summary: A new algorithm for finding minimal perfect hash functions (MPHF) is proposed. The algorithm given three pseudorandom functions \(h_ 0\), \(h_ 1\) and \(h_ 2\), searches for a function \(g\) such that \(F(w)=(h_ 0(w)+g(h_ 1(w))+g(h_ 2(w))) \bmod m\) is a MPHF, where \(m\) is a number of input words.
Zbigniew J. Czech
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Order-preserving minimal perfect hash functions and information retrieval [PDF]
ACM Transactions on Information Systems, 1991 Rapid access to information is essential for a wide variety of retrieval systems and applications. Hashing has long been used when the fastest possible direct search is desired, but is generally not appropriate when sequential or range searches are also required.
Edward A. Fox +3 more
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Balanced families of perfect hash functions and their applications [PDF]
ACM Transactions on Algorithms, 2010 The construction of perfect hash functions is a well-studied topic. In this article, this concept is generalized with the following definition. We say that a family of functions from [ n ] to [ k ] is a δ-balanced ( n,k )-family of perfect hash functions if for every
Noga Alon, Shai Gutner
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Minimal perfect hash functions made simple [PDF]
Communications of the ACM, 1980 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.
Richard J. Cichelli
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A letter oriented minimal perfect hashing function [PDF]
ACM SIGPLAN Notices, 1982 Cichelli has presented a simple method for constructing minimal perfect hash tables of identifiers for small static word sets. The hash function value for a word is computed as the sum of the length of the word and the values associated with the first and last letters of the word.
Curtis R. Cook, R. R. Oldehoeft
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