lemon/suurballe.h
changeset 1638 4e50ed042394
parent 1435 8e85e6bbefdf
child 1875 98698b69a902
equal deleted inserted replaced
0:e9628cd434be 1:032da6d04442
    37   /// The class \ref lemon::Suurballe implements
    37   /// The class \ref lemon::Suurballe implements
    38   /// an algorithm for finding k edge-disjoint paths
    38   /// an algorithm for finding k edge-disjoint paths
    39   /// from a given source node to a given target node in an
    39   /// from a given source node to a given target node in an
    40   /// edge-weighted directed graph having minimal total weight (length).
    40   /// edge-weighted directed graph having minimal total weight (length).
    41   ///
    41   ///
    42   ///\warning Length values should be nonnegative.
    42   ///\warning Length values should be nonnegative!
    43   /// 
    43   /// 
    44   ///\param Graph The directed graph type the algorithm runs on.
    44   ///\param Graph The directed graph type the algorithm runs on.
    45   ///\param LengthMap The type of the length map (values should be nonnegative).
    45   ///\param LengthMap The type of the length map (values should be nonnegative).
    46   ///
    46   ///
    47   ///\note It it questionable whether it is correct to call this method after
    47   ///\note It it questionable whether it is correct to call this method after
   119 
   119 
   120       for(typename Graph::EdgeIt e(G); e!=INVALID; ++e) 
   120       for(typename Graph::EdgeIt e(G); e!=INVALID; ++e) 
   121 	reversed[e] = min_cost_flow.getFlow()[e];
   121 	reversed[e] = min_cost_flow.getFlow()[e];
   122       
   122       
   123       paths.clear();
   123       paths.clear();
   124       //total_length=0;
       
   125       paths.resize(k);
   124       paths.resize(k);
   126       for (int j=0; j<i; ++j){
   125       for (int j=0; j<i; ++j){
   127 	Node n=s;
   126 	Node n=s;
   128 
   127 
   129 	while (n!=t){
   128 	while (n!=t){
   133 	  while (!reversed[e]){
   132 	  while (!reversed[e]){
   134 	    ++e;
   133 	    ++e;
   135 	  }
   134 	  }
   136 	  n = G.target(e);
   135 	  n = G.target(e);
   137 	  paths[j].push_back(e);
   136 	  paths[j].push_back(e);
   138 	  //total_length += length[e];
       
   139 	  reversed[e] = 1-reversed[e];
   137 	  reversed[e] = 1-reversed[e];
   140 	}
   138 	}
   141 	
   139 	
   142       }
   140       }
   143       return i;
   141       return i;
   164 
   162 
   165     ///Checks whether the complementary slackness holds.
   163     ///Checks whether the complementary slackness holds.
   166 
   164 
   167     ///This function checks, whether the given solution is optimal.
   165     ///This function checks, whether the given solution is optimal.
   168     ///Currently this function only checks optimality,
   166     ///Currently this function only checks optimality,
   169     ///doesn't bother with feasibility
   167     ///doesn't bother with feasibility.
   170     ///It is meant for testing purposes.
   168     ///It is meant for testing purposes.
   171     bool checkComplementarySlackness(){
   169     bool checkComplementarySlackness(){
   172       return min_cost_flow.checkComplementarySlackness();
   170       return min_cost_flow.checkComplementarySlackness();
   173     }
   171     }
   174 
   172 
   175     ///Read the found paths.
   173     ///Read the found paths.
   176     
   174     
   177     ///This function gives back the \c j-th path in argument p.
   175     ///This function gives back the \c j-th path in argument p.
   178     ///Assumes that \c run() has been run and nothing changed since then.
   176     ///Assumes that \c run() has been run and nothing has changed since then.
   179     /// \warning It is assumed that \c p is constructed to
   177     /// \warning It is assumed that \c p is constructed to
   180     ///be a path of graph \c G.
   178     ///be a path of graph \c G.
   181     ///If \c j is not less than the result of previous \c run,
   179     ///If \c j is not less than the result of previous \c run,
   182     ///then the result here will be an empty path (\c j can be 0 as well).
   180     ///then the result here will be an empty path (\c j can be 0 as well).
   183     ///
   181     ///
   184     ///\param Path The type of the path structure to put the result to (must meet lemon path concept).
   182     ///\param Path The type of the path structure to put the result to (must meet lemon path concept).
   185     ///\param p The path to put the result to 
   183     ///\param p The path to put the result to.
   186     ///\param j Which path you want to get from the found paths (in a real application you would get the found paths iteratively)
   184     ///\param j Which path you want to get from the found paths (in a real application you would get the found paths iteratively).
   187     template<typename Path>
   185     template<typename Path>
   188     void getPath(Path& p, size_t j){
   186     void getPath(Path& p, size_t j){
   189 
   187 
   190       p.clear();
   188       p.clear();
   191       if (j>paths.size()-1){
   189       if (j>paths.size()-1){