src/lemon/full_graph.h
changeset 1037 3eaff8d04171
parent 985 741f3108a90f
child 1039 bd01c5a3f989
equal deleted inserted replaced
8:ab0bf3ac5d18 9:8c7659fb8ed7
    76     
    76     
    77     /// Maximum edge ID.
    77     /// Maximum edge ID.
    78     ///\sa id(Edge)
    78     ///\sa id(Edge)
    79     int maxId(Edge = INVALID) const { return EdgeNum-1; }
    79     int maxId(Edge = INVALID) const { return EdgeNum-1; }
    80 
    80 
    81     Node tail(Edge e) const { return e.id % NodeNum; }
    81     Node source(Edge e) const { return e.id % NodeNum; }
    82     Node head(Edge e) const { return e.id / NodeNum; }
    82     Node target(Edge e) const { return e.id / NodeNum; }
    83 
    83 
    84 
    84 
    85     /// Node ID.
    85     /// Node ID.
    86     
    86     
    87     /// The ID of a valid Node is a nonnegative integer not greater than
    87     /// The ID of a valid Node is a nonnegative integer not greater than
   134 
   134 
   135     class Edge {
   135     class Edge {
   136       friend class FullGraphBase;
   136       friend class FullGraphBase;
   137       
   137       
   138     protected:
   138     protected:
   139       int id;  // NodeNum * head + tail;
   139       int id;  // NodeNum * target + source;
   140 
   140 
   141       Edge(int _id) : id(_id) {}
   141       Edge(int _id) : id(_id) {}
   142 
   142 
   143       Edge(const FullGraphBase& _graph, int tail, int head) 
   143       Edge(const FullGraphBase& _graph, int source, int target) 
   144 	: id(_graph.NodeNum * head+tail) {}
   144 	: id(_graph.NodeNum * target+source) {}
   145     public:
   145     public:
   146       Edge() { }
   146       Edge() { }
   147       Edge (Invalid) { id = -1; }
   147       Edge (Invalid) { id = -1; }
   148       bool operator==(const Edge edge) const {return id == edge.id;}
   148       bool operator==(const Edge edge) const {return id == edge.id;}
   149       bool operator!=(const Edge edge) const {return id != edge.id;}
   149       bool operator!=(const Edge edge) const {return id != edge.id;}
   248     
   248     
   249     /// Maximum edge ID.
   249     /// Maximum edge ID.
   250     ///\sa id(Edge)
   250     ///\sa id(Edge)
   251     int maxId(Edge = INVALID) const { return EdgeNum-1; }
   251     int maxId(Edge = INVALID) const { return EdgeNum-1; }
   252 
   252 
   253     Node tail(Edge e) const { 
   253     Node source(Edge e) const { 
   254       /// \todo we may do it faster
   254       /// \todo we may do it faster
   255       return ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2; 
   255       return ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2; 
   256     }
   256     }
   257 
   257 
   258     Node head(Edge e) const { 
   258     Node target(Edge e) const { 
   259       int tail = ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2;;
   259       int source = ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2;;
   260       return e.id - (tail) * (tail - 1) / 2; 
   260       return e.id - (source) * (source - 1) / 2; 
   261     }
   261     }
   262 
   262 
   263 
   263 
   264     /// Node ID.
   264     /// Node ID.
   265     
   265     
   313 
   313 
   314     class Edge {
   314     class Edge {
   315       friend class UndirFullGraphBase;
   315       friend class UndirFullGraphBase;
   316       
   316       
   317     protected:
   317     protected:
   318       int id;  // NodeNum * head + tail;
   318       int id;  // NodeNum * target + source;
   319 
   319 
   320       Edge(int _id) : id(_id) {}
   320       Edge(int _id) : id(_id) {}
   321 
   321 
   322       Edge(const UndirFullGraphBase& _graph, int tail, int head) 
   322       Edge(const UndirFullGraphBase& _graph, int source, int target) 
   323 	: id(_graph.NodeNum * head+tail) {}
   323 	: id(_graph.NodeNum * target+source) {}
   324     public:
   324     public:
   325       Edge() { }
   325       Edge() { }
   326       Edge (Invalid) { id = -1; }
   326       Edge (Invalid) { id = -1; }
   327       bool operator==(const Edge edge) const {return id == edge.id;}
   327       bool operator==(const Edge edge) const {return id == edge.id;}
   328       bool operator!=(const Edge edge) const {return id != edge.id;}
   328       bool operator!=(const Edge edge) const {return id != edge.id;}
   349       edge.id = node.id != 0 ? node.id * (node.id - 1) / 2 : -1;
   349       edge.id = node.id != 0 ? node.id * (node.id - 1) / 2 : -1;
   350     }
   350     }
   351 
   351 
   352     /// \todo with specialized iterators we can make faster iterating
   352     /// \todo with specialized iterators we can make faster iterating
   353     void nextOut(Edge& e) const {
   353     void nextOut(Edge& e) const {
   354       int tail = ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2;;
   354       int source = ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2;;
   355       int head = e.id - (tail) * (tail - 1) / 2; 
   355       int target = e.id - (source) * (source - 1) / 2; 
   356       ++head;
   356       ++target;
   357       e.id = head < tail ? tail * (tail - 1) / 2 + head : -1;
   357       e.id = target < source ? source * (source - 1) / 2 + target : -1;
   358     }
   358     }
   359 
   359 
   360     void firstIn(Edge& edge, const Node& node) const {
   360     void firstIn(Edge& edge, const Node& node) const {
   361       edge.id = node.id * (node.id + 1) / 2 - 1;
   361       edge.id = node.id * (node.id + 1) / 2 - 1;
   362     }
   362     }
   363     
   363     
   364     void nextIn(Edge& e) const {
   364     void nextIn(Edge& e) const {
   365       int tail = ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2;;
   365       int source = ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2;;
   366       int head = e.id - (tail) * (tail - 1) / 2; ++head;
   366       int target = e.id - (source) * (source - 1) / 2; ++target;
   367       ++tail;
   367       ++source;
   368       e.id = tail < NodeNum ? tail * (tail - 1) / 2 + head : -1;
   368       e.id = source < NodeNum ? source * (source - 1) / 2 + target : -1;
   369     }
   369     }
   370 
   370 
   371   };
   371   };
   372 
   372 
   373   /// \todo UndirFullGraph from the UndirFullGraphBase
   373   /// \todo UndirFullGraph from the UndirFullGraphBase