alpar@395: // -*- mode:C++ -*-
alpar@395: 
alpar@405: #ifndef HUGO_LIST_GRAPH_H
alpar@405: #define HUGO_LIST_GRAPH_H
alpar@395: 
klao@491: ///\ingroup graphs
alpar@395: ///\file
alpar@405: ///\brief ListGraph, SymListGraph, NodeSet and EdgeSet classes.
alpar@395: 
alpar@395: #include <vector>
deba@698: #include <climits>
alpar@395: 
deba@698: #include "invalid.h"
deba@698: 
deba@703: #include "array_map_factory.h"
deba@698: #include "map_registry.h"
deba@698: 
deba@698: #include "map_defines.h"
alpar@395: 
alpar@395: namespace hugo {
alpar@395: 
alpar@406: /// \addtogroup graphs
alpar@406: /// @{
alpar@406: 
alpar@401:   ///A list graph class.
alpar@395: 
alpar@397:   ///This is a simple and fast erasable graph implementation.
alpar@397:   ///
alpar@395:   ///It conforms to the graph interface documented under
alpar@395:   ///the description of \ref GraphSkeleton.
alpar@395:   ///\sa \ref GraphSkeleton.
alpar@397:   class ListGraph {
alpar@395: 
alpar@397:     //Nodes are double linked.
alpar@397:     //The free nodes are only single linked using the "next" field.
alpar@395:     struct NodeT 
alpar@395:     {
alpar@397:       int first_in,first_out;
alpar@397:       int prev, next;
alpar@397:       //      NodeT() {}
alpar@395:     };
alpar@397:     //Edges are double linked.
alpar@397:     //The free edges are only single linked using the "next_in" field.
alpar@395:     struct EdgeT 
alpar@395:     {
alpar@397:       int head, tail;
alpar@397:       int prev_in, prev_out;
alpar@397:       int next_in, next_out;
alpar@395:       //FIXME: is this necessary?
alpar@397:       //      EdgeT() : next_in(-1), next_out(-1) prev_in(-1), prev_out(-1) {}  
alpar@395:     };
alpar@395: 
alpar@395:     std::vector<NodeT> nodes;
alpar@397:     //The first node
alpar@397:     int first_node;
alpar@397:     //The first free node
alpar@397:     int first_free_node;
alpar@395:     std::vector<EdgeT> edges;
alpar@397:     //The first free edge
alpar@397:     int first_free_edge;
alpar@395:     
alpar@397:   protected:
alpar@395:     
alpar@395:   public:
alpar@397:     
alpar@395:     class Node;
alpar@395:     class Edge;
alpar@395: 
deba@698:     typedef ListGraph Graph;
deba@698: 
alpar@395:   public:
alpar@395: 
alpar@395:     class NodeIt;
alpar@395:     class EdgeIt;
alpar@395:     class OutEdgeIt;
alpar@395:     class InEdgeIt;
alpar@395:     
deba@698:     CREATE_MAP_REGISTRIES;
deba@703:     CREATE_MAPS(ArrayMapFactory);
alpar@395:   public:
alpar@395: 
alpar@397:     ListGraph() : nodes(), first_node(-1),
alpar@397: 		  first_free_node(-1), edges(), first_free_edge(-1) {}
alpar@397:     ListGraph(const ListGraph &_g) : nodes(_g.nodes), first_node(_g.first_node),
alpar@397: 				     first_free_node(_g.first_free_node),
alpar@397: 				     edges(_g.edges),
alpar@397: 				     first_free_edge(_g.first_free_edge) {}
alpar@395:     
alpar@395: 
alpar@395:     int nodeNum() const { return nodes.size(); }  //FIXME: What is this?
alpar@395:     int edgeNum() const { return edges.size(); }  //FIXME: What is this?
alpar@395: 
alpar@695:     ///Set the expected number of edges
alpar@695: 
alpar@695:     ///With this function, it is possible to set the expected number of edges.
alpar@695:     ///The use of this fasten the building of the graph and makes
alpar@695:     ///it possible to avoid the superfluous memory allocation.
alpar@695:     void reserveEdge(int n) { edges.reserve(n); };
alpar@695:     
alpar@395:     ///\bug This function does something different than
alpar@395:     ///its name would suggests...
alpar@395:     int maxNodeId() const { return nodes.size(); }  //FIXME: What is this?
alpar@395:     ///\bug This function does something different than
alpar@395:     ///its name would suggests...
alpar@395:     int maxEdgeId() const { return edges.size(); }  //FIXME: What is this?
alpar@395: 
alpar@395:     Node tail(Edge e) const { return edges[e.n].tail; }
alpar@395:     Node head(Edge e) const { return edges[e.n].head; }
alpar@395: 
alpar@395:     Node aNode(OutEdgeIt e) const { return edges[e.n].tail; }
alpar@395:     Node aNode(InEdgeIt e) const { return edges[e.n].head; }
alpar@395: 
alpar@395:     Node bNode(OutEdgeIt e) const { return edges[e.n].head; }
alpar@395:     Node bNode(InEdgeIt e) const { return edges[e.n].tail; }
alpar@395: 
alpar@395:     NodeIt& first(NodeIt& v) const { 
alpar@395:       v=NodeIt(*this); return v; }
alpar@395:     EdgeIt& first(EdgeIt& e) const { 
alpar@395:       e=EdgeIt(*this); return e; }
alpar@395:     OutEdgeIt& first(OutEdgeIt& e, const Node v) const { 
alpar@395:       e=OutEdgeIt(*this,v); return e; }
alpar@395:     InEdgeIt& first(InEdgeIt& e, const Node v) const { 
alpar@395:       e=InEdgeIt(*this,v); return e; }
alpar@395: 
alpar@395: //     template< typename It >
alpar@395: //     It first() const { It e; first(e); return e; }
alpar@395: 
alpar@395: //     template< typename It >
alpar@395: //     It first(Node v) const { It e; first(e,v); return e; }
alpar@395: 
alpar@395:     bool valid(Edge e) const { return e.n!=-1; }
alpar@395:     bool valid(Node n) const { return n.n!=-1; }
alpar@395:     
alpar@395:     void setInvalid(Edge &e) { e.n=-1; }
alpar@395:     void setInvalid(Node &n) { n.n=-1; }
alpar@395:     
alpar@395:     template <typename It> It getNext(It it) const
alpar@395:     { It tmp(it); return next(tmp); }
alpar@395: 
alpar@395:     NodeIt& next(NodeIt& it) const { 
alpar@397:       it.n=nodes[it.n].next; 
alpar@395:       return it; 
alpar@395:     }
alpar@395:     OutEdgeIt& next(OutEdgeIt& it) const
alpar@395:     { it.n=edges[it.n].next_out; return it; }
alpar@395:     InEdgeIt& next(InEdgeIt& it) const
alpar@395:     { it.n=edges[it.n].next_in; return it; }
alpar@397:     EdgeIt& next(EdgeIt& it) const {
alpar@397:       if(edges[it.n].next_in!=-1) { 
alpar@397: 	it.n=edges[it.n].next_in;
alpar@397:       }
alpar@397:       else {
alpar@397: 	int n;
alpar@397: 	for(n=nodes[edges[it.n].head].next;
alpar@397: 	    n!=-1 && nodes[n].first_in == -1;
alpar@397: 	    n = nodes[n].next) ;
alpar@397: 	it.n = (n==-1)?-1:nodes[n].first_in;
alpar@397:       }
alpar@397:       return it;
alpar@397:     }
alpar@395: 
alpar@395:     int id(Node v) const { return v.n; }
alpar@395:     int id(Edge e) const { return e.n; }
alpar@395: 
alpar@397:     /// Adds a new node to the graph.
alpar@397: 
alpar@397:     /// \todo It adds the nodes in a reversed order.
alpar@397:     /// (i.e. the lastly added node becomes the first.)
alpar@395:     Node addNode() {
alpar@397:       int n;
alpar@397:       
alpar@397:       if(first_free_node==-1)
alpar@397: 	{
alpar@397: 	  n = nodes.size();
alpar@397: 	  nodes.push_back(NodeT());
alpar@397: 	}
alpar@397:       else {
alpar@397: 	n = first_free_node;
alpar@397: 	first_free_node = nodes[n].next;
alpar@397:       }
alpar@397:       
alpar@397:       nodes[n].next = first_node;
alpar@397:       if(first_node != -1) nodes[first_node].prev = n;
alpar@397:       first_node = n;
alpar@397:       nodes[n].prev = -1;
alpar@397:       
alpar@397:       nodes[n].first_in = nodes[n].first_out = -1;
alpar@397:       
alpar@397:       Node nn; nn.n=n;
alpar@395: 
alpar@397:       //Update dynamic maps
deba@698:       node_maps.add(nn);
alpar@395: 
alpar@397:       return nn;
alpar@395:     }
alpar@395:     
alpar@395:     Edge addEdge(Node u, Node v) {
alpar@397:       int n;
alpar@397:       
alpar@397:       if(first_free_edge==-1)
alpar@397: 	{
alpar@397: 	  n = edges.size();
alpar@397: 	  edges.push_back(EdgeT());
alpar@397: 	}
alpar@397:       else {
alpar@397: 	n = first_free_edge;
alpar@397: 	first_free_edge = edges[n].next_in;
alpar@397:       }
alpar@397:       
alpar@397:       edges[n].tail = u.n; edges[n].head = v.n;
alpar@395: 
alpar@397:       edges[n].next_out = nodes[u.n].first_out;
alpar@397:       if(nodes[u.n].first_out != -1) edges[nodes[u.n].first_out].prev_out = n;
alpar@397:       edges[n].next_in = nodes[v.n].first_in;
alpar@397:       if(nodes[v.n].first_in != -1) edges[nodes[v.n].first_in].prev_in = n;
alpar@397:       edges[n].prev_in = edges[n].prev_out = -1;
alpar@397: 	
alpar@397:       nodes[u.n].first_out = nodes[v.n].first_in = n;
alpar@397: 
alpar@397:       Edge e; e.n=n;
alpar@397: 
alpar@397:       //Update dynamic maps
deba@698:       edge_maps.add(e);
alpar@395: 
alpar@395:       return e;
alpar@395:     }
alpar@395: 
alpar@397:   private:
alpar@397:     void eraseEdge(int n) {
alpar@397:       
alpar@397:       if(edges[n].next_in!=-1)
alpar@397: 	edges[edges[n].next_in].prev_in = edges[n].prev_in;
alpar@397:       if(edges[n].prev_in!=-1)
alpar@397: 	edges[edges[n].prev_in].next_in = edges[n].next_in;
alpar@397:       else nodes[edges[n].head].first_in = edges[n].next_in;
alpar@397:       
alpar@397:       if(edges[n].next_out!=-1)
alpar@397: 	edges[edges[n].next_out].prev_out = edges[n].prev_out;
alpar@397:       if(edges[n].prev_out!=-1)
alpar@397: 	edges[edges[n].prev_out].next_out = edges[n].next_out;
alpar@397:       else nodes[edges[n].tail].first_out = edges[n].next_out;
alpar@397:       
alpar@397:       edges[n].next_in = first_free_edge;
alpar@695:       first_free_edge = n;      
alpar@397: 
alpar@397:       //Update dynamic maps
alpar@397:       Edge e; e.n=n;
alpar@397:     }
alpar@397:       
alpar@397:   public:
alpar@397: 
alpar@397:     void erase(Node nn) {
alpar@397:       int n=nn.n;
alpar@397:       
alpar@397:       int m;
alpar@397:       while((m=nodes[n].first_in)!=-1) eraseEdge(m);
alpar@397:       while((m=nodes[n].first_out)!=-1) eraseEdge(m);
alpar@397: 
alpar@397:       if(nodes[n].next != -1) nodes[nodes[n].next].prev = nodes[n].prev;
alpar@397:       if(nodes[n].prev != -1) nodes[nodes[n].prev].next = nodes[n].next;
alpar@397:       else first_node = nodes[n].next;
alpar@397:       
alpar@397:       nodes[n].next = first_free_node;
alpar@397:       first_free_node = n;
alpar@397: 
alpar@397:       //Update dynamic maps
deba@698:       node_maps.erase(nn);
deba@698:      }
deba@698:     
deba@698:     void erase(Edge e) { 
deba@698:       edge_maps.erase(e);
deba@698:       eraseEdge(e.n); 
alpar@397:     }
alpar@397: 
alpar@397:     ///\bug Dynamic maps must be updated!
alpar@397:     ///
alpar@397:     void clear() {
alpar@397:       nodes.clear();edges.clear();
alpar@397:       first_node=first_free_node=first_free_edge=-1;
alpar@397:     }
alpar@395: 
alpar@395:     class Node {
alpar@397:       friend class ListGraph;
alpar@395:       template <typename T> friend class NodeMap;
alpar@400:        
alpar@395:       friend class Edge;
alpar@395:       friend class OutEdgeIt;
alpar@395:       friend class InEdgeIt;
alpar@395:       friend class SymEdge;
alpar@395: 
alpar@395:     protected:
alpar@395:       int n;
alpar@397:       friend int ListGraph::id(Node v) const; 
alpar@395:       Node(int nn) {n=nn;}
alpar@395:     public:
alpar@395:       Node() {}
alpar@503:       Node (Invalid) { n=-1; }
alpar@395:       bool operator==(const Node i) const {return n==i.n;}
alpar@395:       bool operator!=(const Node i) const {return n!=i.n;}
alpar@395:       bool operator<(const Node i) const {return n<i.n;}
alpar@395:     };
alpar@395:     
alpar@395:     class NodeIt : public Node {
alpar@397:       friend class ListGraph;
alpar@395:     public:
alpar@400:       NodeIt() : Node() { }
alpar@400:       NodeIt(Invalid i) : Node(i) { }
alpar@397:       NodeIt(const ListGraph& G) : Node(G.first_node) { }
alpar@579:       ///\todo Undocumented conversion Node -\> NodeIt.
alpar@579:       NodeIt(const ListGraph& G, const Node &n) : Node(n) { }
alpar@395:     };
alpar@395: 
alpar@395:     class Edge {
alpar@397:       friend class ListGraph;
alpar@395:       template <typename T> friend class EdgeMap;
alpar@395: 
alpar@397:       //template <typename T> friend class SymListGraph::SymEdgeMap;      
alpar@397:       //friend Edge SymListGraph::opposite(Edge) const;
alpar@395:       
alpar@395:       friend class Node;
alpar@395:       friend class NodeIt;
alpar@395:     protected:
alpar@395:       int n;
alpar@397:       friend int ListGraph::id(Edge e) const;
alpar@395: 
alpar@395:       Edge(int nn) {n=nn;}
alpar@395:     public:
alpar@395:       Edge() { }
alpar@395:       Edge (Invalid) { n=-1; }
alpar@395:       bool operator==(const Edge i) const {return n==i.n;}
alpar@395:       bool operator!=(const Edge i) const {return n!=i.n;}
alpar@395:       bool operator<(const Edge i) const {return n<i.n;}
alpar@395:       ///\bug This is a workaround until somebody tells me how to
alpar@397:       ///make class \c SymListGraph::SymEdgeMap friend of Edge
alpar@395:       int &idref() {return n;}
alpar@395:       const int &idref() const {return n;}
alpar@395:     };
alpar@395:     
alpar@395:     class EdgeIt : public Edge {
alpar@397:       friend class ListGraph;
alpar@395:     public:
alpar@397:       EdgeIt(const ListGraph& G) : Edge() {
alpar@397:       	int m;
alpar@397: 	for(m=G.first_node;
alpar@397: 	    m!=-1 && G.nodes[m].first_in == -1; m = G.nodes[m].next);
alpar@397: 	n = (m==-1)?-1:G.nodes[m].first_in;
alpar@397:       }
alpar@395:       EdgeIt (Invalid i) : Edge(i) { }
alpar@395:       EdgeIt() : Edge() { }
alpar@395:       ///\bug This is a workaround until somebody tells me how to
alpar@397:       ///make class \c SymListGraph::SymEdgeMap friend of Edge
alpar@395:       int &idref() {return n;}
alpar@395:     };
alpar@395:     
alpar@395:     class OutEdgeIt : public Edge {
alpar@397:       friend class ListGraph;
alpar@395:     public: 
alpar@395:       OutEdgeIt() : Edge() { }
alpar@395:       OutEdgeIt (Invalid i) : Edge(i) { }
alpar@395: 
alpar@397:       OutEdgeIt(const ListGraph& G,const Node v)
alpar@395: 	: Edge(G.nodes[v.n].first_out) {}
alpar@395:     };
alpar@395:     
alpar@395:     class InEdgeIt : public Edge {
alpar@397:       friend class ListGraph;
alpar@395:     public: 
alpar@395:       InEdgeIt() : Edge() { }
alpar@395:       InEdgeIt (Invalid i) : Edge(i) { }
alpar@681:       InEdgeIt(const ListGraph& G,Node v) :Edge(G.nodes[v.n].first_in) {}
alpar@395:     };
alpar@395: 
alpar@395:   };
alpar@395: 
alpar@395:   ///Graph for bidirectional edges.
alpar@395: 
alpar@395:   ///The purpose of this graph structure is to handle graphs
alpar@395:   ///having bidirectional edges. Here the function \c addEdge(u,v) adds a pair
alpar@395:   ///of oppositely directed edges.
alpar@395:   ///There is a new edge map type called
alpar@397:   ///\ref SymListGraph::SymEdgeMap "SymEdgeMap"
alpar@395:   ///that complements this
alpar@395:   ///feature by
alpar@395:   ///storing shared values for the edge pairs. The usual
alpar@395:   ///\ref GraphSkeleton::EdgeMap "EdgeMap"
alpar@395:   ///can be used
alpar@395:   ///as well.
alpar@395:   ///
alpar@395:   ///The oppositely directed edge can also be obtained easily
alpar@395:   ///using \ref opposite.
alpar@397:   ///
alpar@397:   ///Here erase(Edge) deletes a pair of edges.
alpar@397:   ///
alpar@397:   ///\todo this date structure need some reconsiderations. Maybe it
alpar@397:   ///should be implemented independently from ListGraph.
alpar@395: 
deba@701: }
alpar@395: 
alpar@405: #endif //HUGO_LIST_GRAPH_H