The computational complexity of disconnected cut and 2K2-partition

@article{Martin2015TheCC,
  title={The computational complexity of disconnected cut and 2K2-partition},
  author={Barnaby Martin and Dani{\"e}l Paulusma},
  journal={ArXiv},
  year={2015},
  volume={abs/1104.4779}
}
For a connected graph G = ( V , E ) , a subset U ? V is called a disconnected cut if U disconnects the graph and the subgraph induced by U is disconnected as well. We show that the problem to test whether a graph has a disconnected cut is NP-complete. This problem is polynomially equivalent to the following problems: testing if a graph has a 2 K 2 -partition, testing if a graph allows a vertex-surjective homomorphism to the reflexive 4-cycle and testing if a graph has a spanning subgraph that… Expand
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