On fully orientability of 2-degenerate graphs

نویسندگان

  • Hsin-Hao Lai
  • Gerard J. Chang
  • Ko-Wei Lih
چکیده

Suppose that D is an acyclic orientation of the graph G. An arc of D is dependent if its reversal creates a directed cycle. Let d(D) denote the number of dependent arcs in D. Define dmin(G) (dmax(G)) to be the minimum (maximum) number of d(D) over all acyclic orientations D of G. We call G fully orientable if G has an acyclic orientation with exactly k dependent arcs for every k satisfying dmin(G) 6 k 6 dmax(G). We prove that every 2-degenerate graph is fully orientable and give interpretations to their dmin.

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عنوان ژورنال:
  • Inf. Process. Lett.

دوره 105  شماره 

صفحات  -

تاریخ انتشار 2008