klao@946: /* -*- C++ -*-
klao@946:  * src/lemon/graph_utils.h - Part of LEMON, a generic C++ optimization library
klao@946:  *
klao@946:  * Copyright (C) 2004 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
klao@946:  * (Egervary Combinatorial Optimization Research Group, EGRES).
klao@946:  *
klao@946:  * Permission to use, modify and distribute this software is granted
klao@946:  * provided that this copyright notice appears in all copies. For
klao@946:  * precise terms see the accompanying LICENSE file.
klao@946:  *
klao@946:  * This software is provided "AS IS" with no warranty of any kind,
klao@946:  * express or implied, and with no claim as to its suitability for any
klao@946:  * purpose.
klao@946:  *
klao@946:  */
klao@946: 
klao@946: #ifndef LEMON_GRAPH_UTILS_H
klao@946: #define LEMON_GRAPH_UTILS_H
klao@946: 
klao@946: #include <iterator>
klao@946: 
klao@946: #include <lemon/invalid.h>
klao@946: 
alpar@947: ///\ingroup gutils
klao@946: ///\file
alpar@947: ///\brief Graph utilities.
klao@946: ///
klao@946: 
klao@946: 
klao@946: namespace lemon {
klao@946: 
alpar@947: /// \addtogroup gutils
alpar@947: /// @{
alpar@947: 
klao@946:   // counters in the graph
klao@946:   /// \brief Function to count the items in the graph.
klao@946:   ///
klao@946:   /// This function counts the items in the graph.
klao@946:   /// The complexity of the function is O(n) because
klao@946:   /// it iterates on all of the items.
klao@946: 
klao@946:   template <typename Graph, typename ItemIt>
klao@946:   inline int countItems(const Graph& _g) {
klao@946:     int num = 0;
klao@946:     for (ItemIt it(_g); it != INVALID; ++it) {
klao@946:       ++num;
klao@946:     }
klao@946:     return num;
klao@946:   }
klao@946: 
klao@946:   /// \brief Function to count the nodes in the graph.
klao@946:   ///
klao@946:   /// This function counts the nodes in the graph.
klao@946:   /// The complexity of the function is O(n) but for some
klao@946:   /// graph structure it is specialized to O(1).
klao@946: 
klao@946:   template <typename Graph>
klao@946:   inline int countNodes(const Graph& _g) {
klao@946:     return countItems<Graph, typename Graph::NodeIt>(_g);
klao@946:   }
klao@946: 
klao@946:   /// \brief Function to count the edges in the graph.
klao@946:   ///
klao@946:   /// This function counts the edges in the graph.
klao@946:   /// The complexity of the function is O(e) but for some
klao@946:   /// graph structure it is specialized to O(1).
klao@946:   template <typename Graph>
klao@946:   inline int countEdges(const Graph& _g) {
klao@946:     return countItems<Graph, typename Graph::EdgeIt>(_g);
klao@946:   }
klao@946: 
klao@946:   /// \brief Function to count the symmetric edges in the graph.
klao@946:   ///
klao@946:   /// This function counts the symmetric edges in the graph.
klao@946:   /// The complexity of the function is O(e) but for some
klao@946:   /// graph structure it is specialized to O(1).
klao@946:   template <typename Graph>
klao@946:   inline int countSymEdges(const Graph& _g) {
klao@946:     return countItems<Graph, typename Graph::SymEdgeIt>(_g);
klao@946:   }
klao@946: 
klao@946:   template <typename Graph, typename DegIt>
klao@946:   inline int countNodeDegree(const Graph& _g, const typename Graph::Node& _n) {
klao@946:     int num = 0;
klao@946:     for (DegIt it(_g, _n); it != INVALID; ++it) {
klao@946:       ++num;
klao@946:     }
klao@946:     return num;
klao@946:   }
klao@946: 
klao@946:   template <typename Graph>
klao@946:   inline int countOutEdges(const Graph& _g,  const typename Graph::Node& _n) {
klao@946:     return countNodeDegree<Graph, typename Graph::OutEdgeIt>(_g, _n);
klao@946:   }
klao@946: 
klao@946:   template <typename Graph>
klao@946:   inline int countInEdges(const Graph& _g,  const typename Graph::Node& _n) {
klao@946:     return countNodeDegree<Graph, typename Graph::InEdgeIt>(_g, _n);
klao@946:   }
klao@946: 
klao@946:   // graph copy
klao@946: 
klao@946:   template <
klao@946:     typename DestinationGraph, 
klao@946:     typename SourceGraph, 
klao@946:     typename NodeBijection>
klao@946:   void copyNodes(DestinationGraph& _d, const SourceGraph& _s, 
klao@946: 		 NodeBijection& _nb) {    
klao@946:     for (typename SourceGraph::NodeIt it(_s); it != INVALID; ++it) {
klao@946:       _nb[it] = _d.addNode();
klao@946:     }
klao@946:   }
klao@946: 
klao@946:   template <
klao@946:     typename DestinationGraph, 
klao@946:     typename SourceGraph, 
klao@946:     typename NodeBijection,
klao@946:     typename EdgeBijection>
klao@946:   void copyEdges(DestinationGraph& _d, const SourceGraph& _s,
klao@946: 		 const NodeBijection& _nb, EdgeBijection& _eb) {    
klao@946:     for (typename SourceGraph::EdgeIt it(_s); it != INVALID; ++it) {
klao@946:       _eb[it] = _d.addEdge(_nb[_s.tail(it)], _nb[_s.head(it)]);
klao@946:     }
klao@946:   }
klao@946: 
klao@946:   template <
klao@946:     typename DestinationGraph, 
klao@946:     typename SourceGraph, 
klao@946:     typename NodeBijection,
klao@946:     typename EdgeBijection>
klao@946:   void copyGraph(DestinationGraph& _d, const SourceGraph& _s, 
klao@946: 		 NodeBijection& _nb, EdgeBijection& _eb) {
klao@946:     nodeCopy(_d, _s, _nb);
klao@946:     edgeCopy(_d, _s, _nb, _eb);
klao@946:   }
klao@946:  
klao@946:    template <
klao@946:     typename _DestinationGraph, 
klao@946:     typename _SourceGraph, 
klao@946:     typename _NodeBijection 
klao@946:     =typename _SourceGraph::template NodeMap<typename _DestinationGraph::Node>,
klao@946:     typename _EdgeBijection 
klao@946:     =typename _SourceGraph::template EdgeMap<typename _DestinationGraph::Edge>
klao@946:    >
klao@946:    class GraphCopy {
klao@946:    public:
klao@946: 
klao@946:      typedef _DestinationGraph DestinationGraph;
klao@946:      typedef _SourceGraph SourceGraph;
klao@946: 
klao@946:      typedef _NodeBijection NodeBijection;
klao@946:      typedef _EdgeBijection EdgeBijection;
klao@946: 
klao@946:    protected:          
klao@946: 
klao@946:      NodeBijection node_bijection;
klao@946:      EdgeBijection edge_bijection;     
klao@946: 
klao@946:    public:
klao@946:      
klao@946:      GraphCopy(DestinationGraph& _d, const SourceGraph& _s) {
klao@946:        copyGraph(_d, _s, node_bijection, edge_bijection);
klao@946:      }
klao@946: 
klao@946:      const NodeBijection& getNodeBijection() const {
klao@946:        return node_bijection;
klao@946:      }
klao@946: 
klao@946:      const EdgeBijection& getEdgeBijection() const {
klao@946:        return edge_bijection;
klao@946:      }
klao@946:      
klao@946:    };
alpar@947: 
alpar@947: /// @}
alpar@947:   
alpar@947: } //END OF NAMESPACE LEMON
klao@946: 
klao@946: #endif