olemus
graaf, mille kaartel on suund: graaf G = (V,A) , kus
- V on tippude hulk
- A on järjestatud paaride u,v ∈ V hulk
- u on lähtetipp
- v on lõpptipp
=
a graph that is made up of a set of vertices connected by directed edges

näiteid
https://duckduckgo.com/?q=connected+graph&t=h_&iax=images&ia=images

ülevaateid
https://en.wikipedia.org/wiki/Directed_graph

https://enos.itcollege.ee/~jpoial/algorithms/GT/Goodrich_6e_Ch14_Digraphs-handouts.pdf

https://www.cs.princeton.edu/courses/archive/spring14/cos226/lectures/42DirectedGraphs.pdf