lemon/grid_graph.h
changeset 1868 24bf4b8299e7
parent 1791 62e7d237e1fb
child 1875 98698b69a902
equal deleted inserted replaced
4:654f36220a28 5:c2539a65894a
   226     ///
   226     ///
   227     /// If \c prev is \ref INVALID (this is the default value), then
   227     /// If \c prev is \ref INVALID (this is the default value), then
   228     /// It finds the first edge from \c u to \c v. Otherwise it looks for
   228     /// It finds the first edge from \c u to \c v. Otherwise it looks for
   229     /// the next edge from \c u to \c v after \c prev.
   229     /// the next edge from \c u to \c v after \c prev.
   230     /// \return The found edge or INVALID if there is no such an edge.
   230     /// \return The found edge or INVALID if there is no such an edge.
   231     Edge findEdge(Node u, Node v, Edge prev = INVALID) {
   231     Edge findEdge(Node u, Node v, Edge prev = INVALID) const {
   232       if (prev != INVALID) return INVALID;
   232       if (prev != INVALID) return INVALID;
   233       if (v.id - u.id == _width) return Edge(u.id);
   233       if (v.id - u.id == _width) return Edge(u.id);
   234       if (v.id - u.id == 1 && u.id % _width < _width - 1) {
   234       if (v.id - u.id == 1 && u.id % _width < _width - 1) {
   235 	return Edge(u.id / _width * (_width - 1) +
   235 	return Edge(u.id / _width * (_width - 1) +
   236 		    u.id % _width + _edgeLimit);
   236 		    u.id % _width + _edgeLimit);
   347   ///
   347   ///
   348   /// \brief Grid graph class
   348   /// \brief Grid graph class
   349   ///
   349   ///
   350   /// This class implements a special graph type. The nodes of the
   350   /// This class implements a special graph type. The nodes of the
   351   /// graph can be indiced by two integer \c (i,j) value where \c i
   351   /// graph can be indiced by two integer \c (i,j) value where \c i
   352   /// is in the \c [0,height) range and j is in the [0, width) range.
   352   /// is in the \c [0,width) range and j is in the [0, height) range.
   353   /// Two nodes are connected in the graph if the indices differ only
   353   /// Two nodes are connected in the graph if the indices differ only
   354   /// on one position and only one is the difference. 
   354   /// on one position and only one is the difference. 
   355   ///
   355   ///
   356   /// The graph can be indiced in the following way:
   356   /// The graph can be indiced in the following way:
   357   /// \code
   357   /// \code
   358   /// GridGraph graph(h, w);
   358   /// GridGraph graph(w, h);
   359   /// GridGraph::NodeMap<int> val(graph); 
   359   /// GridGraph::NodeMap<int> val(graph); 
   360   /// for (int i = 0; i < graph.width(); ++i) {
   360   /// for (int i = 0; i < graph.width(); ++i) {
   361   ///   for (int j = 0; j < graph.height(); ++j) {
   361   ///   for (int j = 0; j < graph.height(); ++j) {
   362   ///     val[graph(i, j)] = i + j;
   362   ///     val[graph(i, j)] = i + j;
   363   ///   }
   363   ///   }
   451 
   451 
   452     private:
   452     private:
   453       const GridGraph& graph;
   453       const GridGraph& graph;
   454     };
   454     };
   455 
   455 
       
   456     /// \brief Constructor
       
   457     ///
       
   458     /// 
   456     GridGraph(int n, int m) { construct(n, m); }
   459     GridGraph(int n, int m) { construct(n, m); }
   457     
   460     
   458     /// \brief Gives back the edge goes down from the node.
   461     /// \brief Gives back the edge goes down from the node.
   459     ///
   462     ///
   460     /// Gives back the edge goes down from the node. If there is not
   463     /// Gives back the edge goes down from the node. If there is not