Graph 2-Isomorphism is NP-Complete
نویسنده
چکیده
Two graphs G and G' are said to be k-isomorphic if their edge sets can be partitioned into E(G) = ElUE2 u . . . uEk and E(G' > = E-j-U E; IJ l . . IJEk such that as graphs, E i and E! are 1 isomorphic for l. Instance: Set X = {1,2,...,n} and a family $I = (Ai] of 3-element subsets of X . Question: Does & contain an exact cover for X , i.e., a subfamily &' c ,& such that every element of X occurs in exactly one member of ,&' ? Theorem. GC is polynomially transformable to G2I. Therefore, the graph 2-isomorphism problem is NP-complete. J* We follow [3] for the terminology on graphs.
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عنوان ژورنال:
- Inf. Process. Lett.
دوره 9 شماره
صفحات -
تاریخ انتشار 1979