Medians of Graphs and Kings of Tournaments*

نویسندگان

  • Hai-Yen Lee
  • Gerard J. Chang
چکیده

We first prove that for any graph G with a positive vertex weight function w, there exists a graph H with a positive weight function w′ such that w(v) = w′(v) for all vertices v in G and whose w′-median is G. This is a generalization of a previous result for the case in which all weights are 1. The second result is that for any n-tournament T without transmitters, there exists an integer m ≤ 2n−1 and an m-tournament T ′ whose kings are exactly the vertices of T . This improves upon a previous result for m ≤ 2n.

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تاریخ انتشار 1997