A copy of this work was available on the public web and has been preserved in the Wayback Machine. The capture dates from 2020; you can also visit the original URL.
The file type is application/pdf
.
Filters
Minimal perfect hash functions made simple
1980
Communications of the ACM
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 ...
Such functions allow single probe retrieval from minimally sized tables of identifier lists. ...
In several recent articles [2, 3] it has been asserted that in general computing minimal perfect hash functions for static identifier lists (keys) is difficult. ...
doi:10.1145/358808.358813
fatcat:enkohc6p6vhjdaulevvcc7h6e4
Perfect hashing using sparse matrix packing
1990
Information Systems
The perfect hashing function described in this article has been used to create minimal perfect hashing functions for unsegmented word sets of up to 5000 words. ...
This packing algorithm is then applied to create minimal perfect hashing functions for large word lists. ...
Jaeschke [3] developed a reciprocal hashing algorithm for the formation of minimal perfect hashing functions. ...
doi:10.1016/0306-4379(90)90001-6
fatcat:if34q3jf35ab5jnjogs2fb7q7i
Using tries to eliminate pattern collisions in perfect hashing
1994
IEEE Transactions on Knowledge and Data Engineering
Index Tenns-Perfect hashing, minimal perfect hashing, hashing tries, sparse array packing. ...
In this paper, a perfect hashing technique that uses array-based tries and a simple sparse matrix packing algorithm is introduced. ...
A SIMPLE PERFECT HASHING FUNCTION A typical application of a perfect hashing function is the O( 1) retrieval of Pascal reserved words by a Pascal compiler. ...
doi:10.1109/69.277768
fatcat:tw6lneuwmrgffpvf3ikibxaakq
Perfect Hashing for Network Applications
2006
2006 IEEE International Symposium on Information Theory
This motivates us to consider minimal perfect hashing schemes, which reduce the number of memory accesses to just 1 and are also space-efficient. ...
This paper introduces a hardware-friendly scheme for minimal perfect hashing, with space requirement approaching 3.7 times the information theoretic lower bound. ...
A perfect hash function h is minimal if h(S) equals {0, ..., n − 1} [6]. ...
doi:10.1109/isit.2006.261567
dblp:conf/isit/LuPB06
fatcat:sy5pitinxbcjfbsqwrfshhy4by
Optimal table lookup for reserved words in Ada
2006
ACM SIGAda Ada Letters
email asking if I could generate a minimal perfect hashing function (MPHF) for the set of reserved words in Ada 2005. ...
Preamble Recently a colleague wanted to include a section on perfect hashing functions in the latest edition of a book [4] , and after an on-line search brought up a reference of mine [8], he sent me an ...
Cichelli's Idea One of the earliest papers on minimal perfect hashing functions (MPHF) was written by Cichelli [2] . ...
doi:10.1145/1131411.1131414
fatcat:533j2plifvev5ize2sa75v3svm
An optimal algorithm for generating minimal perfect hash functions
1992
Information Processing Letters
A new algorithm for generating order preserving minimal perfect hash functions is presented. The algorithm is probabilistic, involving generation of random graphs. ...
It uses expected linear time and requires a linear number words to represent the hash function, and thus is optimal up to constant factors. It runs very fast in practice. ...
A perfect hash function is an injection h : W → I, where W and I are sets as defined above, k ≥ m. If k = m, then we say that h is a minimal perfect hash function. ...
doi:10.1016/0020-0190(92)90220-p
fatcat:te6smawya5a57lzeelijopovtm
An informal analysis of perfect hash function search
1989
Applied Mathematics Letters
A brief explanation of perfect hash function search is presented followed by an informal analysis of the problem. ...
Perfect hash functions are difficult to find, even when almost minimal solutions are accepted. ...
Cichelli [3] devised an algorithm for computing machine independent, minimal perfect hash functions of the form: hash value = hash key length + associated value of the key'sfirst letter + associated ...
doi:10.1016/0893-9659(89)90071-2
fatcat:o7egspqidnhzfhrgvvfdiebkou
A Practical Minimal Perfect Hashing Method
[chapter]
2005
Lecture Notes in Computer Science
We propose a novel algorithm based on random graphs to construct minimal perfect hash functions h. For a set of n keys, our algorithm outputs h in expected time O(n). ...
This improves the space requirement to 55% of a previous minimal perfect hashing scheme due to Czech, Havas and Majewski. ...
If m = n, that is, the table has the same size as S, then h is a minimal perfect hash function. Minimal perfect hash functions totally avoid the problem of wasted space and time. ...
doi:10.1007/11427186_42
fatcat:66g3nyhgcvc4ll7si4kmrmdz2a
Graphs, hypergraphs and hashing
[chapter]
1994
Lecture Notes in Computer Science
Minimal perfect hash functions are used for memory efficient storage and fast retrieval of items from static sets. ...
Members of the family generate a minimal perfect hash function in two steps. First a special kind of function into an r-graph is computed probabilistically. ...
A perfect hash function is an injection h : W → I, where W and I are sets as defined above, k ≥ m. If k = m, then we say that h is minimal perfect hash function. ...
doi:10.1007/3-540-57899-4_49
fatcat:3xjggn6jhfgqlm226biqvyca5i
Hash and Displace: Efficient Evaluation of Minimal Perfect Hash Functions
1999
BRICS Report Series
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. ...
This improves the probe performance of previous minimal perfect hashing schemes, and is shown to be optimal. ...
minimal hashing is easy. ...
doi:10.7146/brics.v6i13.20070
fatcat:6vhi7vktojcnhc5u34tipbmfzq
Finding and Applying Perfect Hash Functions
1988
Applied Mathematics Letters
Perfect hash functions are difficult to find, even when almost minimal solutions are accepted. ...
be searched using its own perfect hash function. ...
doi:10.1016/0893-9659(88)90168-1
fatcat:n5yjvxo6efhb3ic53prfjdfgde
Shepard: A fast exact match short read aligner
2012
Tenth ACM/IEEE International Conference on Formal Methods and Models for Codesign (MEMCODE2012)
To reduce the hash table size, a minimal perfect hash table is used. ...
The task amounts to a simple string search, allowing for a few mismatches due to mutations and inexact read quality. ...
Minimal Perfect Hash Function Shepard's solution to the large size of hash tables is to use a minimal perfect hash. ...
doi:10.1109/memcod.2012.6292304
dblp:conf/memocode/NelsonTRJZ12
fatcat:uq72mkh2zvdjplbqxgdbzcekoq
Flash memory efficient LTL model checking
2011
Science of Computer Programming
perfect hash function from RAM to flash memory. ...
In contrast to approaches relying on the delayed detection of duplicate states, in this work, we design and exploit appropriate hash functions to re-invent immediate duplicate detection. ...
Acknowledgements We would like to thank Martin Dietzfelbinger for his help to derive the lower bound on perfect hashing, Peter Kissmann for his rigorous proof reading, and the anonymous reviewers for the ...
doi:10.1016/j.scico.2010.03.005
fatcat:5kkssybrs5dibhqgwyhvsv3xfi
Deterministic and efficient minimal perfect hashing schemes
2013
Revista de Informática Teórica e Aplicada
Resumo: Neste trabalho apresentamos versões determinísticas para os esquemas de hashing de Botelho, Kohayakawa e Ziviani (2005) e de Botelho, Pagh e Ziviani (2007). ...
This paper presents deterministic versions to the hashing schemes of Botelho, Kohayakawa and Ziviani (2005) and Botelho, Pagh and Ziviani (2007) , also proves a statement left as open problem in the former ...
1, . . . , n, constructs a minimal perfect hash function in O(n) expected time. ...
doi:10.22456/2175-2745.26905
fatcat:gshnq2dkgrdc3g7xkhtfakq3ka
A faster algorithm for constructing minimal perfect hash functions
1992
Proceedings of the 15th annual international ACM SIGIR conference on Research and development in information retrieval - SIGIR '92
Our previous research on one-probe access to large collections of data indexed by alphanumeric keys has produced the first practical minimal perfect hash functions for this problem. ...
Here, a new algorithm is described for quickly finding minimal perfect hash functions whose specification space is very close to the theoretical lower bound, i.e., around 2 bits per key. ...
, the hash function is called minimal. When both properties hold, one has a minimal perfect hash function (MPHF) as shown at the bottom of Figure 1 . ...
doi:10.1145/133160.133209
dblp:conf/sigir/FoxCH92
fatcat:vysmvejoxvb4vc6jcafoz4hhoy
« Previous
Showing results 1 — 15 out of 12,917 results