No vertices:


Graph with loops and multiple edges, loops considered:
0 1 1 0 1 1 0 0 0

Graph with loops and multiple edges, loops not considered:
0 1 0 0 1 1 0 0 0

Same graph, selecting edge 4:
1

Same graph, but undirected:
1 1 1 1 1 1 1 1 1

Edge out of range.
