Arc

Topics: Graph - Edge

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(definition)

An arc is a directed edge that joins two vertices together.

Given an arc $e$, the head (denoted $head(e)$) is the vertex the arrow points to, while the tail (denoted $tail(e)$) is the vertex the arrow points away from.

Types §

• Given a pair of arcs, we may have recurring or parallel arcs.

• When we have two different arcs that connect a same pair of vertices, but in different directions, we say that they are oppositely directed arcs.

• A multi-arc is a set of two or more arcs that have the same head or tail. The multiplicity of a multi-arc is the number of arcs involved.