In → graph theory, an edge where endpoints are distinguished; one is the head and the other is the tail. A directed edge is specified as an ordered pair of → vertices, u, v and is denoted by (u, v) or u→ v.

→ directed; → edge.

In → graph theory, a graph with → directed edges. Also calle → digraph.

→ directed; → graph.

In a → directed graph, a path in which all → edges are oriented in the same direction.