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Reachability and distance queries via 2-hop labels
The proposed data structure for representing all distances in a graph is distributed in the sense that it may be viewed as assigning labels to the vertices, such that a query involving vertices u and v may be answered using only the labels of u andV.
Labeling dynamic XML trees
Algorithms to label the nodes of an XML tree which is subject to insertions and deletions of nodes are presented and it is proved that their algorithms assign the shortest possible labels which satisfy these requirements.
Reach for A*: Efficient Point-to-Point Shortest Path Algorithms
This work introduces a bidirectional version of the reach-based approach of Gutman [17] that uses implicit lower bounds and adds shortcut arcs to reduce vertex reaches and greatly improves both preprocessing and query times.
Approximation algorithms for asymmetric TSP by decomposing directed regular multigraphs
It is proved that if the d-regular multigraph does not contain more than ⌊d/2⌋ copies of any 2-cycle then it can be found a similar decomposition into n2 pairs of cycle covers where each 2- cycle occurs in at most one component of each pair.
Compact labeling schemes for ancestor queries
This paper proposes a labeling scheme with maximum label size close to 3/2 log n, which is close to the lower bound of log n that follows from the fact that different vertices must have different labels.
Nearest common ancestors: a survey and a new distributed algorithm
A new simple algorithm is presented that labels the nodes of a rooted tree such that from the labels of two nodes alone one can compute in constant time the label of their nearest common ancestor.
Non-price equilibria in markets of discrete goods
An analysis of the welfare properties of mixed-Nash equilibria of the market viewed as a game shows that while pureEquilibrium are always perfectly efficient, mixedEquilibria need not be, and upper and lower bounds on their amount of inefficiency are provided.
Four Strikes Against Physical Mapping of DNA
It is shown that four simplified models of the physical mapping problem lead to NP-complete decision problems: Colored unit interval graph completion, the maximum interval subgraph, the pathwidth of a bipartite graph, and the k-consecutive ones problem for k > or = 2.
Tractability of Parameterized Completion Problems on Chordal, Strongly Chordal, and Proper Interval Graphs
The parameterized complexity of three NP-hard graph completion problems, motivated by molecular biology, is studied and it is shown that the parameterized version of the strongly chordal graph completion problem is FPT by giving an O(ck m log n)-time algorithm for it.
Learning with attribute costs
We study an extension of the "standard" learning models to settings where observing the value of an attribute has an associated cost (which might be different for different attributes). Our model