FindCycle
FindCycle[g] finds a cycle in the graph g.
FindCycle[g,k] finds a cycle of length at most k in the graph g.
FindCycle[g,{k}] finds a cycle of length exactly k.
FindCycle[g,{kmin,kmax}] finds a cycle of length between kmin and kmax.
FindCycle[g,kspec,s] finds at most s cycles.
FindCycle[{g,v},…] finds cycles that include the vertex v.
FindCycle[{v->w,…},…] uses rules v->w to specify the graph g.
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