Marko.Petkovsek@B.GP.CS.CMU.EDU (03/05/90)
I know that the Hamiltonian circuit problem is NP-complete for line graphs. How about COMPLEMENTS of line graphs? A nice equivalent formulation of this problem is the following: INSTANCE: Undirected graph G = (V,E). QUESTION: Is there a cyclic ordering of E in which any two consecutive edges have no vertex in common? I would appreciate any information (or pointers to information) about the complexity of this problem. I couldn't find it in either Garey, Johnson's "Computers and Intractability" or in D.S. Johnson's NP-completeness columns in Journal of Algorithms. Marko.Petkovsek@cs.cmu.edu