Vincenzo Auletta

A 2-Approximation Algorithm for Finding an Optimum 3-Vertex-Connected Spanning Subgraph

The problem of finding a minimum weight k-vertex connected spanning subgraph in a graph G=(V,E) is considered. For k?2, this problem is known to be NP-hard. Combining properties of inclusion-minimal k-vertex connected graphs and of k-out-connected graphs (i.e., graphs which contain a vertex from which there exist k internally vertex-disjoint paths to every other vertex), we derive polynomial time algorithm for finding a (?k/2?+1)-connected subgraph with a weight at most twice the optimum to the original problem. In particular, we obtain a 2-approximation algorithm for the case k=3 of our problem. This improves the best previously known approximation ratio 3. The complexity of the algorithm is O(|V|3|E|)=O(|V|5).

A linear-time algorithm for the feasibility of pebble motion on trees

Abstract. We consider the following pebble motion problem. We are given a tree T with n vertices and two arrangements

Dynamic and static algorithms for optimal placement of resources in a tree

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Metastability of logit dynamics for coordination games

and

Sparse and limited wavelength conversion in all-optical tree networks

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How to route and tax selfish unsplittable traffic

of k<n distinct pebbles numbered 1, . . ., k on distinct vertices of the tree. Pebbles can move along edges of T provided that at any given time at most one pebble is traveling along an edge and each vertex of T contains at most one pebble. We are asked the following question: Is arrangement

Multiple Templates Access of Trees in Parallel Memory Systems

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Logit Dynamics with Concurrent Updates for Local Interaction Games

reachable from

New constructions of mechanisms with verification

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A Linear Time Algorithm for the Feasibility of Pebble Motion on Trees

? We present an algorithm that, on input two arrangements of k pebbles on a tree with n vertices, decides in time O(n) whether the two arrangements are reachable from one another. We also give an algorithm that, on input two reachable configurations, returns a sequence of moves that transforms one configuration into the other. The pebble motion problem on trees has various applications including memory management in distributed systems, robot motion planning, and deflection routing.