VertexInComponentGraph

VertexInComponentGraph[g,{v1,v2,…}] gives the subgraph of the graph g generated by the vertices that have a directed path to at least one of v1,v2,….

VertexInComponentGraph[g,{v1,v2,…},k] gives the subgraph of g generated by vertices with a directed path of at most length k to at least one of v1,v2,….

VertexInComponentGraph[g,{v1,v2,…},{k}] gives the subgraph of g generated by vertices of length exactly k.

VertexInComponentGraph[{v->w,…},…] uses rules v->w to specify the graph g.

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