Journal of Graph Algorithms and Applications
http://jgaa.info ISSN: 1526-1719
DOI: 10.7155/jgaa.00137 The Traveling Salesman Problem for Cubic Graphs David Eppstein Vol. 11, no. 1, pp. 61-81, 2007. Regular paper Abstract We show how to find a Hamiltonian cycle in a graph of degree at most three with n vertices, in time O(2n/3) ≈ 1.260n and linear space. Our algorithm can find the minimum weight Hamiltonian cycle (traveling salesman problem), in the same time bound. We can also count or list all Hamiltonian cycles in a degree three graph in time O(23n/8) ≈ 1.297n. We also solve the traveling salesman problem in graphs of degree at most four, by randomized and deterministic algorithms with runtime O((27/4)n/3) ≈ 1.890n and O((27/4+ϵ)n/3) respectively. Our algorithms allow the input to specify a set of forced edges which must be part of any generated cycle. Our cycle listing algorithm shows that every degree three graph has O(23n/8) Hamiltonian cycles; we also exhibit a family of graphs with 2n/3 Hamiltonian cycles per graph.
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Revised: January 2007. Submitted: April 2004. Communicated by Joseph Mitchell |
Journal of Graph Algorithms and Applications |