Polynomial time recognition of unit circular-arc graphs

We present an efficient algorithm for recognizing unit circular-arc (UCA) graphs, based on a characterization theorem for UCA graphs proved by Tucker in the seventies. Given a proper circular-arc (PCA) graph G, the algorithm starts from a PCA model for G, removes all its circle-covering pairs of arcs and determines whether G is a UCA graph. We also give an O(N) time bound for Tucker's 3/2-approximation algorithm for coloring circular-arc graphs with N vertices, when a circular-arc model is given.

[1]  Robert E. Tarjan,et al.  A Linear-Time Algorithm for a Special Case of Disjoint Set Union , 1985, J. Comput. Syst. Sci..

[2]  A. Tucker,et al.  Matrix characterizations of circular-arc graphs , 1971 .

[3]  Guillermo Durán On some subclasses of circular-arc graphs , 2002 .

[4]  A. Tucker,et al.  Coloring a Family of Circular Arcs , 1975 .

[5]  Ross M. McConnell,et al.  Linear-Time Recognition of Circular-Arc Graphs , 2001, Proceedings 2001 IEEE International Conference on Cluster Computing.

[6]  F. Stahl,et al.  Circular genetic maps , 1967, Journal of cellular physiology.

[7]  Alan Tucker,et al.  Structure theorems for some circular-arc graphs , 1974, Discret. Math..

[8]  Ioannis G. Tollis,et al.  Representations of Graphs on a Cylinder , 1991, SIAM J. Discret. Math..

[9]  Fanica Gavril,et al.  Algorithms on circular-arc graphs , 1974, Networks.

[10]  Clifford Stein,et al.  Introduction to Algorithms, 2nd edition. , 2001 .

[11]  Xiaotie Deng,et al.  Linear-Time Representation Algorithms for Proper Circular-Arc Graphs and Proper Interval Graphs , 1996, SIAM J. Comput..

[12]  K. Stoffers Scheduling of traffic lights—A new approach☆ , 1968 .

[13]  Alan Tucker,et al.  Characterizing circular-arc graphs , 1970 .

[14]  Jens Gustedt,et al.  Efficient Union-Find for Planar Graphs and other Sparse Graph Classes , 1998, Theor. Comput. Sci..

[15]  Lawrence Hubert,et al.  SOME APPLICATIONS OF GRAPH THEORY AND RELATED NON‐METRIC TECHNIQUES TO PROBLEMS OF APPROXIMATE SERIATION: THE CASE OF SYMMETRIC PROXIMITY MEASURES , 1974 .

[16]  Mario Valencia-Pabon,et al.  Revisiting Tucker's Algorithm to Color Circular-Arc Graphs , 2001, Electron. Notes Discret. Math..

[17]  Ronald L. Rivest,et al.  Introduction to Algorithms , 1990 .

[18]  M. Golumbic Algorithmic graph theory and perfect graphs , 1980 .

[19]  Alan C. Tucker,et al.  An Efficient Test for Circular-Arc Graphs , 1980, SIAM J. Comput..