Ejemplo n.º 1
0
  /** Does not handle Graphs of 1 or fewer nodes */
  public Graph kruskal(Graph g) {
    boolean add = false;
    Graph mst = new Graph(); // initialize graph
    Vector edges = g.getEdges(); // get edges

    Collections.sort(edges); // sort edges

    // find mst
    for (int i = 0; i < edges.size(); ++i) {
      Edge edge = (Edge) edges.get(i); // get edge
      KNode[] ends = edge.getEnds(); // get ends
      if (!mst.containsNode(ends[0])) {
        mst.addNode(ends[0]); // check for first end
        add = true;
      }
      if (!mst.containsNode(ends[1])) {
        mst.addNode(ends[1]); // check other end
        add = true;
      }

      if (add) // if either end is new add edge
      {
        mst.addEdge(edge);
        add = false;
      } else // ensure trees are connected if nodes are contained
      {
        if (!mst.pathBetween(ends)) mst.addEdge(edge);
      }
    }

    return mst;
  }
Ejemplo n.º 2
0
  public int compareTo(Object o2) {
    Edge e2 = (Edge) o2;

    if (this.getWeight() < e2.getWeight()) return -1;
    else if (this.getWeight() > e2.getWeight()) return 1;
    else if (this.getWeight() == e2.getWeight()) return 0;
    return -2;
  }
Ejemplo n.º 3
0
  public String printEdges(KNode n) {
    Vector edgeSet = new Vector();

    for (int i = 0; i < edges.size(); ++i) {
      if (((Edge) edges.get(i)).connectsNode(n)) edgeSet.add((Edge) edges.get(i));
    }

    if (edgeSet.size() == 0) return "-none-";

    String value = "";
    for (int i = 0; i < edgeSet.size(); ++i) {
      Edge e = (Edge) edgeSet.get(i);
      value += n + "" + e + "" + e.otherEnd(n) + "\n";
    }
    return value;
  }