public static void cluster( DNVGraph graph, int level)
{
List<DNVNode> untraveledNode = graph.getNodes(level);
List<DNVEdge> untraveledEdge = graph.getEdges(level);
Dk3Calc dk3Calc = new Dk3Calc(graph, level);
DNVGraph compressedGraph = new DNVGraph();
List triangles = hashTableSort.sortKeyDesc(dk3Calc.getTriangles());
List lines = hashTableSort.sortKeyDesc(dk3Calc.getLines());
HashMap<DNVNode, Triangle> parentToTriangle = new HashMap<DNVNode, Triangle>();
HashMap<DNVNode, Line> parentToLine = new HashMap<DNVNode, Line>();