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.