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A graph with directed edges is called a directed graph or diagraph.
Fig: A 3 node directed graph
Directed Walk
A directed walk (or Walk) in a directed graph is a sequence of vertices v0, v1, v2………vk and egdes v0 -> v1, v1 -> v2, ……. vk-1 -> vk.
Directed Acyclic Graph (DAG)
A directed graph is called a Directed Acyclic Graph (DAG) if it does not contain any directed cycles.
Fig: DAG