# Paths, Connectivity

Path and its length in a graph (multigraph) G : A path Î± in G with origin v0 and end vn is an alternating sequence of vertices and edges of the form.

where each edge ei is incident on vertices viâ€“1 and vi. The number of edges, n is called length of Î±. When there is no ambiguity, we denote Î± by its sequence of edges, Î± = (e1, e2, ... en), or by its sequence of vertices Î± = (vo, v1, ..., vn).