if (p2 == null)
continue;
e.add(new Edge(curr, p2, "e" + (c+1)));
c += 2;
}
SubGraph sg1 = new SubGraph(null,v, e, true);
ArrayList<Vertex> v2 = new ArrayList<Vertex>();
ArrayList<Edge> e2 = new ArrayList<Edge>();
Vertex t1 = new Vertex("S");
v2.add(t1);
Vertex t2 = new Vertex("T");
v2.add(t2);
e2.add(new Edge(t1, t2, "e"+c));
SubGraph sg2 = new SubGraph(null,v2, e2, true);
Graph g = new Graph();
g.addSubGraph(0, sg1);
g.addSubGraph(1, sg2);
return g;