arXiv math/03061582003-06-10math.CO

Vertex-partitioning into fixed additive induced-hereditary properties is NP-hard

Alastair Farrugia

备注：: 10 pages, 1 figure, submitted to Electron. J. Combin

英文摘要：

Can the vertices of a graph $G$ be partitioned into $A \cup B$, so that $G[A]$ is a line-graph and $G[B]$ is a forest? Can $G$ be partitioned into a planar graph and a perfect graph? The NP-completeness of these problems are just special cases of our result: if ${\cal P}$ and ${\cal Q}$ are additive induced-hereditary graph properties, then $({\cal P}, {\cal Q})$-colouring is NP-hard, with the sole exception of graph 2-colouring (the case where both $\cal P$ and $\cal Q$ are the set ${\cal O}$ of finite edgeless graphs). Moreover, $({\cal P}, {\cal Q})$-colouring is NP-complete iff ${\cal P}$- and ${\cal Q}$-recognition are both in NP. This proves a conjecture of Kratochv\'ıl and Schiermeyer.

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