1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/demo/coloring.cc	Sat May 14 17:40:45 2005 +0000
     1.3 @@ -0,0 +1,71 @@
     1.4 +#include <vector>
     1.5 +
     1.6 +#include <lemon/smart_graph.h>
     1.7 +#include <lemon/bin_heap.h>
     1.8 +#include <lemon/graph_reader.h>
     1.9 +#include <lemon/graph_to_eps.h>
    1.10 +
    1.11 +using namespace std;
    1.12 +using namespace lemon;
    1.13 +
    1.14 +int main() {
    1.15 +  typedef UndirSmartGraph Graph;
    1.16 +  typedef Graph::Node Node;
    1.17 +  typedef Graph::NodeIt NodeIt;
    1.18 +  typedef Graph::UndirEdge UndirEdge;
    1.19 +  typedef Graph::IncEdgeIt IncEdgeIt;
    1.20 +
    1.21 +  Graph graph;
    1.22 +
    1.23 +  UndirGraphReader<Graph> reader(std::cin, graph);
    1.24 +  Graph::NodeMap<xy<double> > coords(graph);
    1.25 +  reader.readNodeMap("coords", coords);
    1.26 +  
    1.27 +  reader.run();
    1.28 +
    1.29 +  Graph::NodeMap<int> color(graph, -2);
    1.30 +  
    1.31 +  Graph::NodeMap<int> heapMap(graph, -1);
    1.32 +  BinHeap<Node, int, Graph::NodeMap<int> > heap(heapMap);
    1.33 +  
    1.34 +  for (NodeIt it(graph); it != INVALID; ++it) {
    1.35 +    heap.push(it, countOutEdges(graph, it));
    1.36 +  }
    1.37 +
    1.38 +  vector<Node> order;
    1.39 +
    1.40 +  while (!heap.empty()) {
    1.41 +    Node node = heap.top();
    1.42 +    heap.pop();
    1.43 +    color[node] = -1;
    1.44 +    order.push_back(node);
    1.45 +    for (IncEdgeIt it(graph, node); it != INVALID; ++it) {
    1.46 +      Node target = graph.runningNode(it); 
    1.47 +      if (color[target] == -2) {
    1.48 +	heap.decrease(target, heap[target] - 1);
    1.49 +      }
    1.50 +    }
    1.51 +  }
    1.52 +
    1.53 +  for (int i = order.size() - 1; i >= 0; --i) {
    1.54 +    set<int> forbidden;
    1.55 +    for (IncEdgeIt it(graph, order[i]); it != INVALID; ++it) {
    1.56 +      Node target = graph.runningNode(it); 
    1.57 +      if (color[target] != -1) {
    1.58 +	forbidden.insert(color[target]);
    1.59 +      }
    1.60 +    }
    1.61 +    int current = 0;
    1.62 +    while (forbidden.find(current) != forbidden.end()) ++current;
    1.63 +    color[order[i]] = current;
    1.64 +  }
    1.65 +
    1.66 +  ColorSet colorSet;
    1.67 +
    1.68 +  graphToEps(graph, "six_coloring.eps").
    1.69 +    title("Six Colored Graph").copyright("(C) 2005 LEMON Project").
    1.70 +    coords(coords).nodeColors(composeMap(colorSet, color)).
    1.71 +    scaleToA4().run();
    1.72 +
    1.73 +  return 0;
    1.74 +}