Vertex cut

In graph theory, a vertex subset ${\displaystyle S\subset V}$ is a vertex separator (or vertex cut, separating set) for nonadjacent vertices ${\displaystyle a}$ and ${\displaystyle b}$ if the removal of ${\displaystyle S}$ from the graph separates ${\displaystyle a}$ and ${\displaystyle b}$ into distinct connected components.

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