The Computational Complexity of Disconnected Cut and 2K 2-Partition

@inproceedings{Martin2011TheCC,
  title={The Computational Complexity of Disconnected Cut and 2K 2-Partition},
  author={Barnaby Martin and Dani{\"e}l Paulusma},
  booktitle={CP},
  year={2011}
}
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 2K2-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 consists… Expand
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