/ represent a graph as a dict
g:`a`b`e`f`g`h`i`j!(),/:(`b`e`h;`c`f;`d`g;`e`j;`f;`i;`h;`j)

/ keys of loops
loopkeys:{(asc distinct raze x@)over key x}

/ does g have loops?
hasloops:0<count loopkeys@
hasloops g

/ return just the looping subgraphs
loopsof:{key[x]inter/:(key[x]inter loopkeys x)#x}
show loopsof g

\

h/t: nate mcnamara