Journal ArticleDOI
Storing a Sparse Table with 0(1) Worst Case Access Time
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TLDR
A data structure for representing a set of n items from a universe of m items, which uses space n+o(n) and accommodates membership queries in constant time and is easy to implement.Abstract:
A data structure for representing a set of n items from a umverse of m items, which uses space n + o(n) and accommodates membership queries m constant time is described. Both the data structure and the query algorithm are easy to ~mplement.read more
Citations
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Proceedings ArticleDOI
Perfect hashing, graph entropy, and circuit complexity
TL;DR: The information-theoretic notion of graph entropy captures some aspect of the difficulty of computing Boolean functions that is used to derive superlinear lower bounds on the formula size of threshold and other simple Boolean functions.
Proceedings ArticleDOI
Balls and Bins: Smaller Hash Families and Faster Evaluation
TL;DR: The size of families (or, equivalently, the description length of their functions) that guarantee a maximal load of O(log n / log n)) with high probability are studied, as well as the evaluation time of their function.
Journal ArticleDOI
Symmetry Matters for Sizes of Extended Formulations
TL;DR: It is shown that for the polytopes associated with the matchings in the complete graph K_n with $\lfloor\log n\rfloor$ edges there are nonsymmetric extended formulations of polynomial size, while nevertheless no symmetric extended formulation of polynnomial size exist.
Proceedings ArticleDOI
How to distribute a dictionary in a complete network
TL;DR: A distributed dictionary, implemented on a complete, synchronized network of p processors, i.e., randomized RAMs, based on hashing is described and analyzed.
Dissertation
Perceptually based methods for robust image hashing
Brian L. Evans,Vishal Monga +1 more
TL;DR: This dissertation focuses on feature extraction from natural images such that the extracted features are largely invariant under perceptually insignificant modifications to the image (i.e. robust).
References
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Journal ArticleDOI
Should Tables Be Sorted
TL;DR: It is shown that, in a rather general model including al1 the commonly-used schemes, $\lceil $ lg(n+l) $\rceil$ probes to the table are needed in the worst case, provided the key space is sufficiently large.
Journal ArticleDOI
Storing a sparse table
TL;DR: This work proposes a good worst-case method for storing a static table of n entries, each an integer between 0 and N - 1, and analysis shows why a simpler algorithm used for compressing LR parsing tables works so well.
Journal ArticleDOI
Perfect hashing functions: a single probe retrieving method for static sets
TL;DR: A refinement of hashing which allows retrieval of an item in a static table with a single probe is considered, and a rough comparison with ordinary hashing is given which shows that this method can be used conveniently in several practical applications.
Journal ArticleDOI
Reciprocal hashing: a method for generating minimal perfect hashing functions
TL;DR: A method is presented for building minimal perfect hash functions, i.e., functions which allow single probe retrieval from minimally sized tables of identifier sets, and a proof of existence for minimalperfect hash functions of a special type (reciprocal type) is given.