# min_st_separators

##### Minimum size vertex separators

List all vertex sets that are minimal (s,t) separators for some s and t, in an undirected graph.

- Keywords
- graphs

##### Usage

`min_st_separators(graph)`

##### Arguments

- graph
The input graph. It may be directed, but edge directions are ignored.

##### Details

A \((s,t)\) vertex separator is a set of vertices, such that after their removal from the graph, there is no path between \(s\) and \(t\) in the graph.

A \((s,t)\) vertex separator is minimal if none of its subsets is an \((s,t)\) vertex separator.

##### Value

A list of numeric vectors. Each vector contains a vertex set (defined by vertex ids), each vector is an (s,t) separator of the input graph, for some \(s\) and \(t\).

##### References

Anne Berry, Jean-Paul Bordat and Olivier Cogis: Generating All
the Minimal Separators of a Graph, In: Peter Widmayer, Gabriele Neyer and
Stephan Eidenbenz (editors): *Graph-theoretic concepts in computer
science*, 1665, 167--172, 1999. Springer.

##### Examples

```
# NOT RUN {
ring <- make_ring(4)
min_st_separators(ring)
chvatal <- make_graph("chvatal")
min_st_separators(chvatal)
# }
```

*Documentation reproduced from package igraph, version 1.2.4.2, License: GPL (>= 2)*