src/work/marci/bfs_iterator.h
changeset 551 d167149bde95
parent 415 679e64913c5e
child 560 5adcef1d7bcc
equal deleted inserted replaced
6:094bd4b5b3fe 7:dc4bebaeaed0
    26       own_reached_map(false) { }
    26       own_reached_map(false) { }
    27     BfsIterator(const Graph& _graph) : 
    27     BfsIterator(const Graph& _graph) : 
    28       graph(&_graph), reached(*(new ReachedMap(*graph /*, false*/))), 
    28       graph(&_graph), reached(*(new ReachedMap(*graph /*, false*/))), 
    29       own_reached_map(true) { }
    29       own_reached_map(true) { }
    30     ~BfsIterator() { if (own_reached_map) delete &reached; }
    30     ~BfsIterator() { if (own_reached_map) delete &reached; }
    31     //s is marcked reached.
    31     /// This method markes s reached.
    32     //if the queue is empty, then the its is pushed ant the first OutEdgeIt is processe.
    32     /// If the queue is empty, then s is pushed in the bfs queue 
    33     //is the queue is not empty, then is it pushed.
    33     /// and the first OutEdgeIt is processed.
       
    34     /// If the queue is not empty, then s is simply pushed.
    34     void pushAndSetReached(Node s) { 
    35     void pushAndSetReached(Node s) { 
    35       reached.set(s, true);
    36       reached.set(s, true);
    36       if (bfs_queue.empty()) {
    37       if (bfs_queue.empty()) {
    37 	bfs_queue.push(s);
    38 	bfs_queue.push(s);
    38 	graph->first(actual_edge, s);
    39 	graph->first(actual_edge, s);
    48 	} 
    49 	} 
    49       } else {
    50       } else {
    50 	bfs_queue.push(s);
    51 	bfs_queue.push(s);
    51       }
    52       }
    52     }
    53     }
       
    54     /// As \c BfsIterator<Graph, ReachedMap> works as an edge-iterator, 
       
    55     /// its \c operator++() iterates on the edges in a bfs order.
    53     BfsIterator<Graph, /*OutEdgeIt,*/ ReachedMap>& 
    56     BfsIterator<Graph, /*OutEdgeIt,*/ ReachedMap>& 
    54     operator++() { 
    57     operator++() { 
    55       if (graph->valid(actual_edge)) { 
    58       if (graph->valid(actual_edge)) { 
    56 	graph->next(actual_edge);
    59 	graph->next(actual_edge);
    57 	if (graph->valid(actual_edge)) {
    60 	if (graph->valid(actual_edge)) {
    81 	}
    84 	}
    82       }
    85       }
    83       return *this;
    86       return *this;
    84     }
    87     }
    85     bool finished() const { return bfs_queue.empty(); }
    88     bool finished() const { return bfs_queue.empty(); }
       
    89     /// The conversion operator makes for converting the bfs-iterator 
       
    90     /// to an \c out-edge-iterator.
    86     operator OutEdgeIt() const { return actual_edge; }
    91     operator OutEdgeIt() const { return actual_edge; }
    87     bool isBNodeNewlyReached() const { return b_node_newly_reached; }
    92     bool isBNodeNewlyReached() const { return b_node_newly_reached; }
    88     bool isANodeExamined() const { return !(graph->valid(actual_edge)); }
    93     bool isANodeExamined() const { return !(graph->valid(actual_edge)); }
    89     Node aNode() const { return bfs_queue.front(); }
    94     Node aNode() const { return bfs_queue.front(); }
    90     Node bNode() const { return graph->bNode(actual_edge); }
    95     Node bNode() const { return graph->bNode(actual_edge); }
    91     const ReachedMap& getReachedMap() const { return reached; }
    96     const ReachedMap& getReachedMap() const { return reached; }
    92     const std::queue<Node>& getBfsQueue() const { return bfs_queue; }
    97     const std::queue<Node>& getBfsQueue() const { return bfs_queue; }
    93   };  
    98   };  
    94 
    99 
    95   /// Bfs searches from s for the nodes wich are not marked in 
   100   /// Bfs searches from s for the nodes wich are not marked in 
    96   /// reachedmap
   101   /// \c reached_map
       
   102   /// Reached is a read-write bool-map, Pred is a write-nodemap 
       
   103   /// and dist is an rw-nodemap, have to be.
    97   template <typename Graph, 
   104   template <typename Graph, 
    98 	    typename ReachedMap=typename Graph::template NodeMap<bool>, 
   105 	    typename ReachedMap=typename Graph::template NodeMap<bool>, 
    99 	    typename PredMap
   106 	    typename PredMap
   100 	    =typename Graph::template NodeMap<typename Graph::Edge>, 
   107 	    =typename Graph::template NodeMap<typename Graph::Edge>, 
   101 	    typename DistMap=typename Graph::template NodeMap<int> > 
   108 	    typename DistMap=typename Graph::template NodeMap<int> > 
   105     typedef typename Parent::Node Node;
   112     typedef typename Parent::Node Node;
   106     PredMap& pred;
   113     PredMap& pred;
   107     DistMap& dist;
   114     DistMap& dist;
   108   public:
   115   public:
   109     Bfs<Graph, ReachedMap, PredMap, DistMap>(const Graph& _graph, ReachedMap& _reached, PredMap& _pred, DistMap& _dist) : BfsIterator<Graph, ReachedMap>(_graph, _reached), pred(&_pred), dist(&_dist) { }
   116     Bfs<Graph, ReachedMap, PredMap, DistMap>(const Graph& _graph, ReachedMap& _reached, PredMap& _pred, DistMap& _dist) : BfsIterator<Graph, ReachedMap>(_graph, _reached), pred(&_pred), dist(&_dist) { }
   110     //s is marked to be reached and pushed in the bfs queue.
   117     /// s is marked to be reached and pushed in the bfs queue.
   111     //if the queue is empty, then the first out-edge is processed
   118     /// If the queue is empty, then the first out-edge is processed.
   112     //If s was not marked previously, then 
   119     /// If s was not marked previously, then 
   113     //in addition its pred is set to be INVALID, and dist to 0. 
   120     /// in addition its pred is set to be INVALID, and dist to 0. 
   114     //if s was marked previuosly, then it is simply pushed.
   121     /// if s was marked previuosly, then it is simply pushed.
   115     void push(Node s) { 
   122     void push(Node s) { 
   116       if (this->reached[s]) {
   123       if (this->reached[s]) {
   117 	Parent::pushAndSetReached(s);
   124 	Parent::pushAndSetReached(s);
   118       } else {
   125       } else {
   119 	Parent::pushAndSetReached(s);
   126 	Parent::pushAndSetReached(s);
   120 	pred.set(s, INVALID);
   127 	pred.set(s, INVALID);
   121 	dist.set(s, 0);
   128 	dist.set(s, 0);
   122       }
   129       }
   123     }
   130     }
       
   131     /// A bfs is processed from s.
   124     void run(Node s) {
   132     void run(Node s) {
   125       push(s);
   133       push(s);
   126       while (!this->finished()) this->operator++();
   134       while (!this->finished()) this->operator++();
   127     }
   135     }
   128     Bfs<Graph, ReachedMap, PredMap, DistMap> operator++() {
   136     Bfs<Graph, ReachedMap, PredMap, DistMap> operator++() {
   198     Node bNode() const { return graph->bNode(actual_edge); }
   206     Node bNode() const { return graph->bNode(actual_edge); }
   199     const ReachedMap& getReachedMap() const { return reached; }
   207     const ReachedMap& getReachedMap() const { return reached; }
   200     const std::stack<OutEdgeIt>& getDfsStack() const { return dfs_stack; }
   208     const std::stack<OutEdgeIt>& getDfsStack() const { return dfs_stack; }
   201   };
   209   };
   202 
   210 
       
   211   /// Dfs searches from s for the nodes wich are not marked in 
       
   212   /// \c reached_map
       
   213   /// Reached is a read-write bool-map, Pred is a write-nodemap, have to be.
       
   214   template <typename Graph, 
       
   215 	    typename ReachedMap=typename Graph::template NodeMap<bool>, 
       
   216 	    typename PredMap
       
   217 	    =typename Graph::template NodeMap<typename Graph::Edge> > 
       
   218   class Dfs : public DfsIterator<Graph, ReachedMap> {
       
   219     typedef DfsIterator<Graph, ReachedMap> Parent;
       
   220   protected:
       
   221     typedef typename Parent::Node Node;
       
   222     PredMap& pred;
       
   223   public:
       
   224     Dfs<Graph, ReachedMap, PredMap>(const Graph& _graph, ReachedMap& _reached, PredMap& _pred) : DfsIterator<Graph, ReachedMap>(_graph, _reached), pred(&_pred) { }
       
   225     /// s is marked to be reached and pushed in the bfs queue.
       
   226     /// If the queue is empty, then the first out-edge is processed.
       
   227     /// If s was not marked previously, then 
       
   228     /// in addition its pred is set to be INVALID. 
       
   229     /// if s was marked previuosly, then it is simply pushed.
       
   230     void push(Node s) { 
       
   231       if (this->reached[s]) {
       
   232 	Parent::pushAndSetReached(s);
       
   233       } else {
       
   234 	Parent::pushAndSetReached(s);
       
   235 	pred.set(s, INVALID);
       
   236       }
       
   237     }
       
   238     /// A bfs is processed from s.
       
   239     void run(Node s) {
       
   240       push(s);
       
   241       while (!this->finished()) this->operator++();
       
   242     }
       
   243     Dfs<Graph, ReachedMap, PredMap> operator++() {
       
   244       Parent::operator++();
       
   245       if (this->graph->valid(this->actual_edge) && this->b_node_newly_reached) 
       
   246       {
       
   247 	pred.set(this->bNode(), this->actual_edge);
       
   248       }
       
   249       return *this;
       
   250     }
       
   251     const PredMap& getPredMap() const { return pred; }
       
   252   };
       
   253 
       
   254 
   203 } // namespace hugo
   255 } // namespace hugo
   204 
   256 
   205 #endif //HUGO_BFS_ITERATOR_H
   257 #endif //HUGO_BFS_ITERATOR_H