// -*- c++ -*- 

 #ifndef MAP_BITS_H

 #define MAP_BITS_H

 ///\ingroup graphmaps

 ///\file

 ///\brief Some utils to help implement maps.

 namespace hugo {

   /// \addtogroup graphmaps

   /// @{

   /// Helper class to get information about the key type.

   template <typename Graph, typename KeyIt>

   struct KeyInfo {};

   template <typename Graph>

   struct KeyInfo<Graph, typename Graph::NodeIt> {

     static int maxId(const Graph& graph) {

       return graph.maxNodeId();

     }

     static int id(const Graph& graph, const typename Graph::Node& node) {

       return graph.id(node);

     }

   };

   template <typename Graph>

   struct KeyInfo<Graph, typename Graph::EdgeIt> {

     static int maxId(const Graph& graph) {

       return graph.maxEdgeId();

     }

     static int id(const Graph& graph, const typename Graph::Edge& edge) {

       return graph.id(edge);

     }

   };

   template <typename Graph>

   struct KeyInfo<Graph, typename Graph::SymEdgeIt> {

     static int maxId(const Graph& graph) {

       return graph.maxEdgeId() >> 1;

     }

     static int id(const Graph& graph, const typename Graph::Edge& edge) {

       return graph.id(edge) >> 1;

     }

   };

   /// @}

 }

 #endif