
16
Complex Networks: An Algorithmic Perspective
Figure 2.7: a) A weighted graph. b) A directed graph
E
′
= {(x
0
,x
1
),(x
1
,x
2
),..., (x
k−1
,x
k
)}. A path is usually refereed by the sequence of
its vertices. A cycle is a path that starts and ends at the same vertex and visits each
vertex exactly once and has at least a length of 3. The length of a cycle is the number
of vertices it has. The minimum length of a cycle in a graph G is called its girth, if
there is a cycle. When G does not have any cycle, the girth is defined as 0. A chord
of a graph G(V,E) is an edge e ∈E which joins two vertices of a cycle in G but is not
included in the cycle. A