1.1 --- a/src/demo/sub_graph_wrapper_demo.cc	Thu Sep 16 14:01:36 2004 +0000
     1.2 +++ b/src/demo/sub_graph_wrapper_demo.cc	Thu Sep 16 14:27:27 2004 +0000
     1.3 @@ -2,6 +2,8 @@
     1.4  
     1.5  // Use a DIMACS max flow file as stdin.
     1.6  // sub_graph_wrapper_demo < dimacs_max_flow_file
     1.7 +// This program computes a maximum number of disjoint shortest paths
     1.8 +// between s and t.
     1.9  
    1.10  #include <iostream>
    1.11  #include <fstream>
    1.12 @@ -46,16 +48,21 @@
    1.13    Dijkstra dijkstra(g, length);
    1.14    dijkstra.run(s);
    1.15  
    1.16 +  // This map returns true exactly for those edges which are 
    1.17 +  // tight w.r.t the length funcion and the potential 
    1.18 +  // given by the dijkstra algorithm.
    1.19    typedef TightEdgeFilterMap<Graph, const Dijkstra::DistMap, LengthMap> 
    1.20      TightEdgeFilter;
    1.21    TightEdgeFilter tight_edge_filter(g, dijkstra.distMap(), length);
    1.22  
    1.23    ConstMap<Node, bool> const_true_map(true);
    1.24 +  // This graph contains exaclty the tight edges.
    1.25    typedef SubGraphWrapper<Graph, ConstMap<Node, bool>, TightEdgeFilter> SubGW;
    1.26    SubGW gw(g, const_true_map, tight_edge_filter);
    1.27  
    1.28    ConstMap<Edge, int> const_1_map(1);
    1.29    Graph::EdgeMap<int> flow(g, 0);
    1.30 +  // Max flow between s and t in the graph of tight edges.
    1.31    Preflow<SubGW, int, ConstMap<Edge, int>, Graph::EdgeMap<int> > 
    1.32      preflow(gw, s, t, const_1_map, flow);
    1.33    preflow.run();