[1422] | 1 | #include <vector> |
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| 2 | |
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| 3 | #include <lemon/smart_graph.h> |
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| 4 | #include <lemon/bin_heap.h> |
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| 5 | #include <lemon/graph_reader.h> |
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| 6 | #include <lemon/graph_to_eps.h> |
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| 7 | |
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| 8 | using namespace std; |
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| 9 | using namespace lemon; |
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| 10 | |
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| 11 | int main() { |
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| 12 | typedef UndirSmartGraph Graph; |
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| 13 | typedef Graph::Node Node; |
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| 14 | typedef Graph::NodeIt NodeIt; |
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| 15 | typedef Graph::UndirEdge UndirEdge; |
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| 16 | typedef Graph::IncEdgeIt IncEdgeIt; |
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| 17 | |
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| 18 | Graph graph; |
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| 19 | |
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| 20 | UndirGraphReader<Graph> reader(std::cin, graph); |
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| 21 | Graph::NodeMap<xy<double> > coords(graph); |
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| 22 | reader.readNodeMap("coords", coords); |
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| 23 | |
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| 24 | reader.run(); |
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| 25 | |
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| 26 | Graph::NodeMap<int> color(graph, -2); |
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| 27 | |
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| 28 | Graph::NodeMap<int> heapMap(graph, -1); |
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| 29 | BinHeap<Node, int, Graph::NodeMap<int> > heap(heapMap); |
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| 30 | |
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| 31 | for (NodeIt it(graph); it != INVALID; ++it) { |
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| 32 | heap.push(it, countOutEdges(graph, it)); |
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| 33 | } |
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| 34 | |
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| 35 | vector<Node> order; |
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| 36 | |
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| 37 | while (!heap.empty()) { |
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| 38 | Node node = heap.top(); |
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| 39 | heap.pop(); |
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| 40 | color[node] = -1; |
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| 41 | order.push_back(node); |
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| 42 | for (IncEdgeIt it(graph, node); it != INVALID; ++it) { |
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| 43 | Node target = graph.runningNode(it); |
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| 44 | if (color[target] == -2) { |
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| 45 | heap.decrease(target, heap[target] - 1); |
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| 46 | } |
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| 47 | } |
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| 48 | } |
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| 49 | |
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| 50 | for (int i = order.size() - 1; i >= 0; --i) { |
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| 51 | set<int> forbidden; |
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| 52 | for (IncEdgeIt it(graph, order[i]); it != INVALID; ++it) { |
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| 53 | Node target = graph.runningNode(it); |
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| 54 | if (color[target] != -1) { |
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| 55 | forbidden.insert(color[target]); |
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| 56 | } |
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| 57 | } |
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| 58 | int current = 0; |
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| 59 | while (forbidden.find(current) != forbidden.end()) ++current; |
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| 60 | color[order[i]] = current; |
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| 61 | } |
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| 62 | |
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| 63 | ColorSet colorSet; |
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| 64 | |
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| 65 | graphToEps(graph, "six_coloring.eps"). |
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| 66 | title("Six Colored Graph").copyright("(C) 2005 LEMON Project"). |
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| 67 | coords(coords).nodeColors(composeMap(colorSet, color)). |
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| 68 | scaleToA4().run(); |
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| 69 | |
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| 70 | return 0; |
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| 71 | } |
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