Classes of Interval Digraphs and 0 , 1 -
نویسندگان
چکیده
We consider a hierarchy of four classes of interval digraphs, or equivalently four classes of 0,1-matrics. We provide forbidden submatrix characterizations separating the successive classes. The largest class is the set of (adjacency matrices of) interval digraphs; the smallest is the set of (adjacency matrices of) unit interval digraphs.
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