Showing papers in "Journal of Algorithms in 1996"

TL;DR: It is shown that the duality of a pair of monotone disjunctive normal forms of sizencan be tested inno(logn)time.

TL;DR: An efficient incremental algorithm for the single-source shortest-path problem with positive edge lengths is obtained and is able to handle “multiple heterogeneous modifications”: between updates, the input graph is allowed to be restructured by an arbitrary mixture of edge insertions, edge deletions, and edge-length changes.

TL;DR: For all constantsk,l, explicit algorithms that, given a graphG=(V,E) with a tree-decomposition ofG with treewidth with useO(|V|) time are given, which do not rely on non-constructive reasoning and are single exponential inkandl.

TL;DR: It is shown that with recently developed derandomization techniques, one can convert Clarkson’s randomized algorithm for linear programming in fixed dimension into a linear-time deterministic algorithm, which works in a fairly general abstract setting, which allows us to solve various other problems.

TL;DR: The performance of two algorithms, GUC and SC, are considered, when applied to a random instance ?

TL;DR: The bounds for computing a network decomposition distributively and deterministically are improved and it is shown that the class of graphs G whose maximum degree isnO(?(n))where ?

TL;DR: In this paper, the authors consider the online multiprocessor scheduling problem first considered by Graham in 1966 and present an algorithm CHASM? that outperforms all previously published algorithms for anym?8 and has a competitive ratio of at most 1.945 for allm(the best known lower bound is 1.837).

TL;DR: In this article, a new problem called α-connectivity is introduced and its complexity gradually increases as the value of α grows, and the complexity jumps if the value α becomes a bit larger.

TL;DR: A data structure that can store a set of disjoint fat objects ind-space such that point location and bounded-size range searching with arbitrarily shaped ranges can be performed efficiently is presented.

TL;DR: The problem of finding minimum-weight spanning subgraphs with a given connectivity requirement is considered and a constant factor approximation algorithm is given assuming that the edge-weights satisfy the triangle inequality.

TL;DR: These algorithms can be used to implement a simulation strategy for anyNprocessor PRAM on a restartable fail-stop CRCW PRAM such that it guarantees a terminating execution of each simulatedNprocessor step, withO(log2N) overhead ratio, andO(min{N+Plog2N+MlogN,N·P0.59}) (subquadratic) completed work (whereMis the number of failures during this step's simulation).

TL;DR: A new model of computation is presented which assumes that it is possible to determine the true evolutionary tree for each three species, perhaps through the use of Ahlquist?Sibley experimental techniques and presents tight upper and lower bounds for constructing evolutionary trees using experiments.

TL;DR: This work achieves anO(logn) amortized time bound per operation for the off-line version of the dynamic convex hull problem in the plane, where each insert instruction adds a new point to the set, each delete instruction removes an existing point, and each query requests a standard conveX hull search.

TL;DR: Algorithms for the recognition of greedy instances of certain problems, structural characterization of such instances for other problems, and proofs ofNP-hardness of the recognition problem for some other cases are presented.

TL;DR: A polynomial algorithm is presented for schedulingnjobs on a single machine that is continuously available from time zero onward and that can handle no more than one job at a time and these can be used if precedence constraints exist between the jobs or if all penalty functions are nonincreasing in the job completion times.

TL;DR: This work describes polynomial time algorithms thatwhp(i) find a Hamilton cycle inG, and (ii) approximately count the number of Hamilton cycles inG.

TL;DR: Two algorithms are presented for the more general problem of ranking and unranking rooted spanning arborescences of a directed graph and the number of arithmetic operations can be reduced to the same as that of the best known algorithms for matrix multiplication.

TL;DR: The tree-decomposition algorithm enables us to construct efficient parallel algorithms for a broad class of problems, when restricted to graphs of tree-width at mostw, many of these problems areNP-complete for general graphs.

TL;DR: A linear-time sequential algorithm and an optimal parallel algorithm which find an edge-coloring of a given partialk-tree with the minimum number of colors for fixedk are given.

TL;DR: First, it is proved that this problem of finding a minimum-length schedule for a set of unit-length tasks with a forest of intrees as precedence relation is NP-complete; second, a linear time algorithm is derived for the special case thatmequals 2.

TL;DR: It is shown that the problem of augmenting outerplanar graphs by adding a minimum number of edges such that the augmented graph is planar and bridge-connected, biconnected, or triconsnected can be solved in linear time and space.

TL;DR: A good approximation to the probability of a large deviation from the mean of the basic quicksort is given and it is found that this probability is quite small.

TL;DR: This paper presents an efficient parallel algorithms for families of graphs, where a separator decomposition either is provided with the input or is easily obtainable, and presents anNCalgorithm that computes shortest-paths from sources to all other vertices using O(n3?+s(n+n2?)) work.

TL;DR: This paper presents efficient algorithms for finding a core of a tree with a specified length using O(log2n) time usingO(n) processors on an EREW PRAM model.

TL;DR: It is shown that for layered graphs of widthkand any ?

TL;DR: This paper provides worst case examples that meet the known upper bound for additional values of M, and shows tightness for certain values of the parameterM, and proves an asymptotic worst case ratio of 12/7 for the classical bin packing problem and improves lower bounds for some interesting cases that are left open.

TL;DR: The purpose of this note is to prove that the distribution of ranks after allocation is the same as the Distribution of search distances in uniform hashing, when the rank-orderings are independent and uniformly random.

TL;DR: The Gauss algorithm for the reduction of two-dimensional lattices from thel2-norm to arbitrary norms is generalized and Vallee's analysis is extended to the generalized algorithm.

TL;DR: It is shown that if the authors allow onlyO(n) space, a ray shooting query among a collection of disjoint simple polygons can be answered in timeO(?m/formula]?1+?log2n) time, for any ?>0.

TL;DR: It is proved that deciding isomorphism of directed path graphs is isomorphic complete, whereas for rooteddirected path graphs the algorithm presented is a polynomial-time isomorphisms algorithm.