Finding Nonseparating Induced Cycles and Independent Spanning Trees in 3-Connected Graphs

Abstract Given a vertex r of a 3-connected graph G , we show how to find three independent spanning trees of G rooted at r . Our proof is based on showing that every 3-connected graph has a nonseparating ear decomposition. This extends Whitney's characterisation that a graph is 2-connected iff it has an ear decomposition. We also show that a nonseparating ear decomposition can be constructed in O ( VE ) time, and hence, three independent spanning trees can be found in O ( VE ) time. We construct a nonseparating ear decomposition by solving the following problem at most V times. Given an edge tr and a vertex u of a 3-connected graph G , find a nonseparating induced cycle of G through tr and avoiding u . W. T. Tutte (Proc. London Math. Soc. 13 (1963), 743–767) first showed that such a cycle can always be found. We give a linear time algorithm for this.

[1]  Carsten Thomassen,et al.  Non-separating induced cycles in graphs , 1981, J. Comb. Theory, Ser. B.

[2]  W. Mader über minimaln-fach zusammenhängende, unendliche Graphen und ein Extremalproblem , 1972 .

[3]  Bela Bollobas,et al.  Graph theory , 1979 .

[4]  A. P. Domoryad The Four-Colour Problem , 1963 .

[5]  William T. Tutte,et al.  A theory of 3-connected graphs , 1961 .

[6]  Frank Harary,et al.  Graph Theory , 2016 .

[7]  W. T. Tutte How to Draw a Graph , 1963 .

[8]  S. Gill Williamson,et al.  Depth-First Search and Kuratowski Subgraphs , 1984, JACM.

[9]  Robert E. Tarjan,et al.  Data structures and network algorithms , 1983, CBMS-NSF regional conference series in applied mathematics.

[10]  László Lovász,et al.  Connectivity Algorithms Using Rubber-bands , 1986, Foundations of Software Technology and Theoretical Computer Science.

[11]  Shimon Even,et al.  Graph Algorithms , 1979 .

[12]  Danny Dolev,et al.  A new look at fault tolerant network routing , 1984, STOC '84.

[13]  Robert E. Tarjan,et al.  Efficient Planarity Testing , 1974, JACM.

[14]  Robert E. Tarjan,et al.  Dividing a Graph into Triconnected Components , 1973, SIAM J. Comput..

[15]  B. Bollobás,et al.  Extremal Graph Theory , 2013 .

[16]  Alon Itai,et al.  The Multi-Tree Approach to Reliability in Distributed Networks , 1984, Inf. Comput..