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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Indexing and querying color sets of images
TL;DR: The set of color sets of continuous regions of an image given as a matrix of m rows over n ź m columns where each element in the matrix is an integer from 1, ź named a color is studied.
Thirty nine years of stratified trees
TL;DR: The historical backgrounds against which the stratified trees were discovered and implemented are described; they can be found in the various textbooks and papers mentioned, including a Wikipedia page.
Posted Content
String Indexing for Patterns with Wildcards
TL;DR: In this paper, a linear space index with query time O(m+\sigma^j \log \log n + occ) was proposed, which is the first non-trivial bound with this query time.
Space-efficient data structures for string searching and retrieval
TL;DR: Top-k Framework: Converting Top-k to Thrive via Logarithmic Sketch and Differentially Encoding a Sorted Array.
Posted Content
Sparse Regular Expression Matching
Philip Bille,Inge Li Gørtz +1 more
TL;DR: This work presents the first algorithm for regular expression matching that can take advantage of sparsity in the input instance of the position automaton, and improves the best known bounds forregular expression matching by almost a linear factor in the density of the problem.
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.