/**
* .
*
* @return a graph
*/
public Pseudograph<String, DefaultEdge> create() {
Pseudograph<String, DefaultEdge> g = new Pseudograph<String, DefaultEdge>(DefaultEdge.class);
assertEquals(0, g.vertexSet().size());
g.addVertex(V1);
assertEquals(1, g.vertexSet().size());
g.addVertex(V2);
assertEquals(2, g.vertexSet().size());
g.addVertex(V3);
assertEquals(3, g.vertexSet().size());
g.addVertex(V4);
assertEquals(4, g.vertexSet().size());
assertEquals(0, g.edgeSet().size());
e1 = g.addEdge(V1, V2);
assertEquals(1, g.edgeSet().size());
e2 = g.addEdge(V2, V3);
assertEquals(2, g.edgeSet().size());
e3 = g.addEdge(V3, V1);
assertEquals(3, g.edgeSet().size());
e3_b = g.addEdge(V3, V1);
assertEquals(4, g.edgeSet().size());
assertNotNull(e3_b);
u = g.addEdge(V1, V1);
assertEquals(5, g.edgeSet().size());
u = g.addEdge(V1, V1);
assertEquals(6, g.edgeSet().size());
return g;
}
