Journal ArticleDOI
Storing a Sparse Table with 0(1) Worst Case Access Time
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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
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Proceedings Article
Derandomization Via Small Sample Spaces (Abstract)
TL;DR: Many randomized algorithms run successfully even when the random choices they utilize are not fully independent, so it is possible to replace the appropriate exponentially large sample spaces required to simulate all random choices of the algorithms by ones of polynomial size, to derandomize the algorithms.
Book ChapterDOI
Optimally managing the history of an evolving forest
TL;DR: An optimal, dynamic algorithm is proposed that reconstructs the state of any subtree in the forest at a given instant t in the past, in O(|s(t)|+loglogT) time, where s(t) is the cardinality of the requested subtree and T is the total length of the evolution.
Book ChapterDOI
Element distinctness and sorting on one-tape off-line turing machines
TL;DR: It is shown that the Element Distinctness Problem (EDP) for m binary strings of length l = O(m/log2m) can be solved in time O( m3/2l1/2) and space O(northern) on a nondeterministic machine.
Posted Content
Better size estimation for sparse matrix products
TL;DR: This algorithm combines the size estimation technique of Bar-Yossef et al. with a particular class of pairwise independent hash functions that allows the sketch of a set of the form to be computed in expected time and I/Os, and matches a space lower bound shown in that paper.
On the Complexity of a Game Related to the Dictionary Problem
TL;DR: In this paper, a game on trees that is related to the dictionary problem is considered, where two players, A and B, which take turns, modifies the tree by adding new leaves and replacing subtrees.
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.