Adjacency Matrix/Examples/Loop-Multigraph

Example of Adjacency Matrix
The elements of the adjacency matrix of a loop-multigraph are integers, and this time some of the diagonal elements are non-zero:

$\qquad \begin{pmatrix} 0 & 2 & 0 & 0 & 0 & 0 \\ 2 & 0 & 1 & 1 & 0 & 0 \\ 0 & 1 & 2 & 1 & 0 & 0 \\ 0 & 1 & 1 & 2 & 0 & 1 \\ 0 & 0 & 0 & 0 & 0 & 3 \\ 0 & 0 & 0 & 1 & 3 & 0 \\ \end{pmatrix}$