String graphs. II. recognizing string graphs is NP-hard
نویسندگان
چکیده
منابع مشابه
Recognizing tough graphs is NP-hard
We consider only undirected graphs without loops or multiple edges. Our terminology and notation will be standard except as indicated; a good reference for any undefined terms is [2]. We will use c(G) to denote the number of components of a graph G. Chvtital introduced the notion of tough graphs in [3]. Let t be any positive real number. A graph G is said to be t-tough if tc(G-X)5 JXJ for all X...
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ژورنال
عنوان ژورنال: Journal of Combinatorial Theory, Series B
سال: 1991
ISSN: 0095-8956
DOI: 10.1016/0095-8956(91)90091-w