IncidenceList

IncidenceList[g,v] gives a list of edges incident to vertex v.

IncidenceList[g,patt] gives a list of edges incident to vertices that match the pattern patt.

IncidenceList[g,patt,d] gives a list of incident edges d steps away.

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

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