## A SIMPLE LINEAR ALGORITHM FOR THE CONNECTED DOMINATION PROBLEM IN CIRCULAR-ARC GRAPHS

Ruo-Wei Hung and Maw-Shang Chang

Department of Computer Science and Information Engineering
National Chung Cheng University
Ming-Hsiung, Chiayi 621, Taiwan, R.O.C.
e-mail: {rwhung,mschang}@cs.ccu.edu.tw

## Abstract

A connected dominating set of a graph G = (V,E) is a subset of vertices CD ⊆ V such that every vertex not in CD is adjacent to at least one vertex in CD, and the subgraph induced by CD is connected. We show that, given an arc family F with endpoints sorted, a minimum-cardinality connected dominating set of the circular-arc graph constructed from F can be computed in O(| F| ) time.

Keywords: graph algorithms, circular-arc graphs, connected dominating set, shortest path.

2000 Mathematics Subject Classification: 05C85, 05C69.

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Received 18 March 2002
Revised 18 January 2003