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Showing papers in "Journal of Algorithms in 2004"


Journal ArticleDOI
TL;DR: It is shown that there are graphs with optimal labels of length 3 log n, such that if the authors use any labels with fewer than n bits per label, computing the distance function requires exponential time.

369 citations


Journal ArticleDOI
TL;DR: A polynomial-time approximation scheme for k-partial vertex cover on planar graphs, and for covering k points in Rd by disks is obtained, and an approximation of 4/3 is obtained.

203 citations


Journal ArticleDOI
TL;DR: In this article, it was shown that O(log Δ) bits of memory suffice to explore any tree of maximum degree Δ if stopping is not required, and that bounded memory is not sufficient to explore with stop all trees of bounded degree.

163 citations


Journal ArticleDOI
TL;DR: A fast deterministic algorithm for integer sorting in linear space in O(n log log n) time and linear space which improves previous best deterministic sorting algorithm and improves the result of Andersson et al.

159 citations


Journal ArticleDOI
TL;DR: The string matching with mismatches problem as discussed by the authors is that of finding the number of mismatches between a pattern P of length m and every length m substring of the text T.

155 citations


Journal ArticleDOI
TL;DR: A (2 - 2/k) approximation algorithm is presented for the node multiway cut problem, thus matching the result of Dahlhaus et al. for the edge version of this problem.

151 citations


Journal ArticleDOI
TL;DR: General techniques that allow to develop algorithms with running time c√k|G|, given an instance G of a problem on planar graphs with parameter k are discussed, and extensions of the speed-up technique to basically all fixed-parameter tractable planar graph problems are exhibited.

116 citations


Journal ArticleDOI
TL;DR: If uniform agreement is required, one additional round is needed to decide, and so uniform consensus is also harder than consensus for crash failures, based on a new lower bound result for the synchronous model that is state for the uniform consensus problem.

108 citations


Journal ArticleDOI
TL;DR: The first sublinear average space universal compact routing schemes for directed networks are presented and they bound the maximum sized table at each node by O(kn(3k+1)/(2ċ3k)).

95 citations


Journal ArticleDOI
TL;DR: The data structure presented here is a simplification of the cache-oblivious B-tree of Bender, Demaine, and Farach-Colton and has memory performance optimized for all levels of the memory hierarchy even though it has no memory-hierarchy-specific parameterization.

93 citations


Journal ArticleDOI
TL;DR: In this paper, the authors considered the problem of partitioning disk graphs of bounded radius ratio and showed that the problem is fixed parameter tractable with running time 2O(√k) + nO(1) for a given set of n disks in the Euclidean plane, where k is a set of k non-intersecting disks.

Journal ArticleDOI
TL;DR: A deterministic, polynomial-time algorithm with domination ratio 1 - o(1) for the partition problem, and an algoritiun with domination ratios Ω(1), for the MaxCut problem and for some far-reaching extensions of it, including Max-r-Sat, for each fixed r.

Journal ArticleDOI
TL;DR: This work provides an all-norm 2-approximation polynomial algorithm for the restricted assignment problem and shows that for any given lp norm (p > 1) there is no PTAS unless P=NP by showing an APX-hardness result.

Journal ArticleDOI
TL;DR: An efficient parameterized algorithm solving the Set Packing problem, in which it is assumed that the size of the sets is bounded by m and the algorithm is fixed-parameter tractable.

Journal ArticleDOI
TL;DR: In this article, an improved semidefinite programming based approximation algorithm for the MAX CUT problem in graphs of maximum degree at most 3 was presented, and the approximation ratio of the new algorithm is at least 0.9326.

Journal ArticleDOI
TL;DR: Two algorithms are presented for the problem of finding a minimum transversal in a hypergraph of rank 3, also known as the 3-Hitting Set problem, which is a natural extension of the vertex cover problem for ordinary graphs.

Journal ArticleDOI
TL;DR: It is shown that on planar undirected graphs the problems of computing a multi-way graph separation and single source shortest paths can be reduced I/O-efficiently to planar breadth-first search (BFS).

Journal ArticleDOI
TL;DR: In this article, a linear-time algorithm is given to examine whether a planar graph G of maximum degree three has a rectangular drawing or not, and to find a rectangle drawing of G if it exists.

Journal ArticleDOI
TL;DR: It is shown that the radio broadcast problem is Ω(log n)-inapproximable unless NP ⊆ BPTIME (nO(log log n)), the first result on the hardness of approximation of this problem.

Journal ArticleDOI
TL;DR: An algorithm for the dominating set problem with time complexity O((4g+40)kn2) for graphs of bounded genus g ≥ 1, where k is the size of the set.

Journal ArticleDOI
An Zhu1
TL;DR: It is proved that the bounded delay model with uniform delay 2 is equivalent to a modified FIFO preemptive model with queue size 2, and improved upper and lower bounds are given on the 2-uniform bounded Delay model, matching the previously known upper bound.

Journal ArticleDOI
TL;DR: This research proposes an O(rN2) time and O(N2 log N) space algorithm to design a minimum-distortion quantizer of r levels for a random variable drawn from an alphabet of size N and shows that for a very large class of distortion measures the objective function of optimal multi-resolution quantization satisfies the convex Monge property.

Journal ArticleDOI
TL;DR: This paper initiates the extra-resource analysis of EDF for overloaded systems, showing that EDF supplemented with a simple form of admission control can provide a similar performance guarantee in both the single and multi-processor settings.

Journal ArticleDOI
TL;DR: The problem of finding several users with the same optimization goal is addressed by the problem of establishing a conference call between mobile users and it is proved that a natural heuristic is an e/(e - 1 )-approximation solution.

Journal ArticleDOI
TL;DR: In this paper, the authors presented a polynomial time approximation algorithm for the asymmetric maximum traveling salesperson problem that achieves performance ratio 8/13 (1 - 1/n).

Journal ArticleDOI
Matthew Andrews1, Lisa Zhang1
TL;DR: A randomized work-conserving scheme that guarantees, with high probability, an additive delay bound of approximately 1/ρi + Ki, which is smaller than the multiplicative bound of WFQ, especially when the hop count Ki is large.

Journal ArticleDOI
TL;DR: In this article, the authors consider the problem of restructuring an ordered binary tree T, preserving the in-order sequence of its nodes, so as to reduce its height to some target value h.

Journal ArticleDOI
TL;DR: It is proved that splay trees are competitive to any such class of dynamic trees-noticing that so far s play trees had been proven competitive only w.r.t, static structures like trees and sorted tables with a finger, or exponentially faster than dynamic linear structures like a 'move-to-front' self-adjusting list.

Journal ArticleDOI
TL;DR: This work considers the inverse parametric sequence alignment problem, where a sequence alignment is given and the task is to determine parameter values such that the reference alignment is optimal for those parameter values.

Journal ArticleDOI
TL;DR: A variant of the Seat Reservation Problem in which seat changes are allowed is considered and Min-Change, which will ask passengers to change seats, only if they would otherwise have been rejected, is proposed and shown to seat all passengers if the optimal off-line algorithm could have accommodated them with only half as many seats.