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Reachability and distance queries via 2-hop labels
TLDR
We propose a new data structure for representing all distances in a graph that is based on 2-hop covers of the shortest paths, or of all paths, in the graph. Expand
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Labeling dynamic XML trees
TLDR
We present algorithms to label the nodes of an XML tree which is subject to insertions and deletions of nodes. Expand
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Approximation algorithms for asymmetric TSP by decomposing directed regular multigraphs
TLDR
We prove that if the d-regular multigraph does not contain more than ⌊d/2⌋ copies of any 2-cycles then we can find a similar decomposition into n2 pairs of cycle covers where each 2-cycle occurs in at most one component of each pair. Expand
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Compact labeling schemes for ancestor queries
We consider the following problem. Give a rooted tree T, label the nodes of T in the most compact way such that given the labels of two nodes one can determine in constant time, by looking only atExpand
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Nearest common ancestors: a survey and a new distributed algorithm
TLDR
A new algorithm 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. Expand
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Reach for A*: Efficient Point-to-Point Shortest Path Algorithms
TLDR
We study the point-to-point shortest path problem in a setting where preprocessing is allowed. Expand
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Four Strikes Against Physical Mapping of DNA
TLDR
We show that four simplified models of the problem lead to NP-complete decision problems: Colored unit interval graph completion, the maximum interval (or unit interval) subgraph, the pathwidth of a bipartite graph, and the k-consecutive ones problem. Expand
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Non-price equilibria in markets of discrete goods
TLDR
We study markets of indivisible items in which price-based (Walrasian) equilibria often do not exist due to the discrete non-convex setting. Expand
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Tractability of Parameterized Completion Problems on Chordal, Strongly Chordal, and Proper Interval Graphs
We study the parameterized complexity of three NP-hard graph completion problems. The minimum fill-in problem asks if a graph can be triangulated by adding at most k edges. We develop O(ck m) andExpand
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Faster and simpler algorithm for sorting signed permutations by reversals
TLDR
We give a quadratic algorithm for finding the minimum number of reversals needed to sort a signed permutation. Expand
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