VertexInComponent

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

VertexInComponent[g,{v1,v2,…},{k}] gives the vertices at length exactly k.

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

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