A sink of a Digraph D is a vertex of D that has no children. That is, v is a sink of D if and only if there are only edges pointing into v; none can be pointing out (there is no edge of the form (v,u)).
i1 : D = digraph({a,b,c,d,e},{{a,b},{b,c},{b,d},{e,b}});
|
i2 : sinks D
o2 = {c, d}
o2 : List
|
The object sinks is a method function.