src/work/bfs_iterator.hh
changeset 52 a4fc9c5dcee5
child 58 f71840c04b2a
equal deleted inserted replaced
-1:000000000000 0:ef9b80aedf9d
       
     1 #ifndef MARCI_BFS_HH
       
     2 #define MARCI_BFS_HH
       
     3 
       
     4 #include <queue>
       
     5 #include <stack>
       
     6 
       
     7 namespace marci {
       
     8 
       
     9   template <typename Graph>
       
    10   struct bfs {
       
    11     typedef typename Graph::NodeIt NodeIt;
       
    12     typedef typename Graph::EdgeIt EdgeIt;
       
    13     typedef typename Graph::EachNodeIt EachNodeIt;
       
    14     typedef typename Graph::OutEdgeIt OutEdgeIt;
       
    15     Graph& G;
       
    16     NodeIt s;
       
    17     typename Graph::NodeMap<bool> reached;
       
    18     typename Graph::NodeMap<EdgeIt> pred;
       
    19     typename Graph::NodeMap<int> dist;
       
    20     std::queue<NodeIt> bfs_queue;
       
    21     bfs(Graph& _G, NodeIt _s) : G(_G), s(_s), reached(_G), pred(_G), dist(_G) { 
       
    22       bfs_queue.push(s); 
       
    23       for(EachNodeIt i=G.template first<EachNodeIt>(); i.valid(); ++i) 
       
    24 	reached.set(i, false);
       
    25       reached.set(s, true);
       
    26       dist.set(s, 0); 
       
    27     }
       
    28     
       
    29     void run() {
       
    30       while (!bfs_queue.empty()) {
       
    31 	NodeIt v=bfs_queue.front();
       
    32 	OutEdgeIt e=G.template first<OutEdgeIt>(v);
       
    33 	bfs_queue.pop();
       
    34 	for( ; e.valid(); ++e) {
       
    35 	  NodeIt w=G.bNode(e);
       
    36 	  std::cout << "scan node " << G.id(w) << " from node " << G.id(v) << std::endl;
       
    37 	  if (!reached.get(w)) {
       
    38 	    std::cout << G.id(w) << " is newly reached :-)" << std::endl;
       
    39 	    bfs_queue.push(w);
       
    40 	    dist.set(w, dist.get(v)+1);
       
    41 	    pred.set(w, e);
       
    42 	    reached.set(w, true);
       
    43 	  } else {
       
    44 	    std::cout << G.id(w) << " is already reached" << std::endl;
       
    45 	  }
       
    46 	}
       
    47       }
       
    48     }
       
    49   };
       
    50 
       
    51   template <typename Graph> 
       
    52   struct bfs_visitor {
       
    53     typedef typename Graph::NodeIt NodeIt;
       
    54     typedef typename Graph::EdgeIt EdgeIt;
       
    55     typedef typename Graph::OutEdgeIt OutEdgeIt;
       
    56     Graph& G;
       
    57     bfs_visitor(Graph& _G) : G(_G) { }
       
    58     void at_previously_reached(OutEdgeIt& e) { 
       
    59       //NodeIt v=G.aNode(e);
       
    60       NodeIt w=G.bNode(e);
       
    61       std::cout << G.id(w) << " is already reached" << std::endl;
       
    62    }
       
    63     void at_newly_reached(OutEdgeIt& e) { 
       
    64       //NodeIt v=G.aNode(e);
       
    65       NodeIt w=G.bNode(e);
       
    66       std::cout << G.id(w) << " is newly reached :-)" << std::endl;
       
    67     }
       
    68   };
       
    69 
       
    70   template <typename Graph, typename ReachedMap, typename visitor_type>
       
    71   struct bfs_iterator {
       
    72     typedef typename Graph::NodeIt NodeIt;
       
    73     typedef typename Graph::EdgeIt EdgeIt;
       
    74     typedef typename Graph::OutEdgeIt OutEdgeIt;
       
    75     Graph& G;
       
    76     std::queue<OutEdgeIt>& bfs_queue;
       
    77     ReachedMap& reached;
       
    78     visitor_type& visitor;
       
    79     void process() {
       
    80       while ( !bfs_queue.empty() && !bfs_queue.front().valid() ) { bfs_queue.pop(); } 
       
    81       if (bfs_queue.empty()) return;
       
    82       OutEdgeIt e=bfs_queue.front();
       
    83       //NodeIt v=G.aNode(e);
       
    84       NodeIt w=G.bNode(e);
       
    85       if (!reached.get(w)) {
       
    86 	visitor.at_newly_reached(e);
       
    87 	bfs_queue.push(G.template first<OutEdgeIt>(w));
       
    88 	reached.set(w, true);
       
    89       } else {
       
    90 	visitor.at_previously_reached(e);
       
    91       }
       
    92     }
       
    93     bfs_iterator(Graph& _G, std::queue<OutEdgeIt>& _bfs_queue, ReachedMap& _reached, visitor_type& _visitor) : G(_G), bfs_queue(_bfs_queue), reached(_reached), visitor(_visitor) { 
       
    94       //while ( !bfs_queue.empty() && !bfs_queue.front().valid() ) { bfs_queue.pop(); } 
       
    95       valid();
       
    96     }
       
    97     bfs_iterator<Graph, ReachedMap, visitor_type>& operator++() { 
       
    98       //while ( !bfs_queue.empty() && !bfs_queue.front().valid() ) { bfs_queue.pop(); } 
       
    99       //if (bfs_queue.empty()) return *this;
       
   100       if (!valid()) return *this;
       
   101       ++(bfs_queue.front());
       
   102       //while ( !bfs_queue.empty() && !bfs_queue.front().valid() ) { bfs_queue.pop(); } 
       
   103       valid();
       
   104       return *this;
       
   105     }
       
   106     //void next() { 
       
   107     //  while ( !bfs_queue.empty() && !bfs_queue.front().valid() ) { bfs_queue.pop(); } 
       
   108     //  if (bfs_queue.empty()) return;
       
   109     //  ++(bfs_queue.front());
       
   110     //  while ( !bfs_queue.empty() && !bfs_queue.front().valid() ) { bfs_queue.pop(); } 
       
   111     //}
       
   112     bool valid() { 
       
   113       while ( !bfs_queue.empty() && !bfs_queue.front().valid() ) { bfs_queue.pop(); } 
       
   114       if (bfs_queue.empty()) return false; else return true;
       
   115     }
       
   116     //bool finished() { 
       
   117     //  while ( !bfs_queue.empty() && !bfs_queue.front().valid() ) { bfs_queue.pop(); } 
       
   118     //  if (bfs_queue.empty()) return true; else return false;
       
   119     //}
       
   120     operator EdgeIt () { return bfs_queue.front(); }
       
   121 
       
   122   };
       
   123 
       
   124   template <typename Graph, typename ReachedMap>
       
   125   struct bfs_iterator1 {
       
   126     typedef typename Graph::NodeIt NodeIt;
       
   127     typedef typename Graph::EdgeIt EdgeIt;
       
   128     typedef typename Graph::OutEdgeIt OutEdgeIt;
       
   129     Graph& G;
       
   130     std::queue<OutEdgeIt>& bfs_queue;
       
   131     ReachedMap& reached;
       
   132     bool _newly_reached;
       
   133     bfs_iterator1(Graph& _G, std::queue<OutEdgeIt>& _bfs_queue, ReachedMap& _reached) : G(_G), bfs_queue(_bfs_queue), reached(_reached) { 
       
   134       valid();
       
   135       if (!bfs_queue.empty() && bfs_queue.front().valid()) { 
       
   136 	OutEdgeIt e=bfs_queue.front();
       
   137 	NodeIt w=G.bNode(e);
       
   138 	if (!reached.get(w)) {
       
   139 	  bfs_queue.push(G.template first<OutEdgeIt>(w));
       
   140 	  reached.set(w, true);
       
   141 	  _newly_reached=true;
       
   142 	} else {
       
   143 	  _newly_reached=false;
       
   144 	}
       
   145       }
       
   146     }
       
   147     bfs_iterator1<Graph, ReachedMap>& operator++() { 
       
   148       if (!valid()) return *this;
       
   149       ++(bfs_queue.front());
       
   150       valid();
       
   151       if (!bfs_queue.empty() && bfs_queue.front().valid()) { 
       
   152 	OutEdgeIt e=bfs_queue.front();
       
   153 	NodeIt w=G.bNode(e);
       
   154 	if (!reached.get(w)) {
       
   155 	  bfs_queue.push(G.template first<OutEdgeIt>(w));
       
   156 	  reached.set(w, true);
       
   157 	  _newly_reached=true;
       
   158 	} else {
       
   159 	  _newly_reached=false;
       
   160 	}
       
   161       }
       
   162       return *this;
       
   163     }
       
   164     bool valid() { 
       
   165       while ( !bfs_queue.empty() && !bfs_queue.front().valid() ) { bfs_queue.pop(); } 
       
   166       if (bfs_queue.empty()) return false; else return true;
       
   167     }
       
   168     operator OutEdgeIt() { return bfs_queue.front(); }
       
   169     //ize
       
   170     bool newly_reached() { return _newly_reached; }
       
   171 
       
   172   };
       
   173 
       
   174   template <typename Graph, typename OutEdgeIt, typename ReachedMap>
       
   175   struct BfsIterator {
       
   176     typedef typename Graph::NodeIt NodeIt;
       
   177     Graph& G;
       
   178     std::queue<OutEdgeIt>& bfs_queue;
       
   179     ReachedMap& reached;
       
   180     bool b_node_newly_reached;
       
   181     OutEdgeIt actual_edge;
       
   182     BfsIterator(Graph& _G, 
       
   183 		std::queue<OutEdgeIt>& _bfs_queue, 
       
   184 		ReachedMap& _reached) : 
       
   185       G(_G), bfs_queue(_bfs_queue), reached(_reached) { 
       
   186       actual_edge=bfs_queue.front();
       
   187       if (actual_edge.valid()) { 
       
   188 	NodeIt w=G.bNode(actual_edge);
       
   189 	if (!reached.get(w)) {
       
   190 	  bfs_queue.push(G.firstOutEdge(w));
       
   191 	  reached.set(w, true);
       
   192 	  b_node_newly_reached=true;
       
   193 	} else {
       
   194 	  b_node_newly_reached=false;
       
   195 	}
       
   196       }
       
   197     }
       
   198     BfsIterator<Graph, OutEdgeIt, ReachedMap>& 
       
   199     operator++() { 
       
   200       if (bfs_queue.front().valid()) { 
       
   201 	++(bfs_queue.front());
       
   202 	actual_edge=bfs_queue.front();
       
   203 	if (actual_edge.valid()) {
       
   204 	  NodeIt w=G.bNode(actual_edge);
       
   205 	  if (!reached.get(w)) {
       
   206 	    bfs_queue.push(G.firstOutEdge(w));
       
   207 	    reached.set(w, true);
       
   208 	    b_node_newly_reached=true;
       
   209 	  } else {
       
   210 	    b_node_newly_reached=false;
       
   211 	  }
       
   212 	}
       
   213       } else {
       
   214 	bfs_queue.pop(); 
       
   215 	actual_edge=bfs_queue.front();
       
   216 	if (actual_edge.valid()) {
       
   217 	  NodeIt w=G.bNode(actual_edge);
       
   218 	  if (!reached.get(w)) {
       
   219 	    bfs_queue.push(G.firstOutEdge(w));
       
   220 	    reached.set(w, true);
       
   221 	    b_node_newly_reached=true;
       
   222 	  } else {
       
   223 	    b_node_newly_reached=false;
       
   224 	  }
       
   225 	}
       
   226       }
       
   227       return *this;
       
   228     }
       
   229     bool finished() { return bfs_queue.empty(); }
       
   230     operator OutEdgeIt () { return actual_edge; }
       
   231     bool bNodeIsNewlyReached() { return b_node_newly_reached; }
       
   232     bool aNodeIsExamined() { return !(actual_edge.valid()); }
       
   233   };
       
   234 
       
   235 
       
   236   template <typename Graph, typename OutEdgeIt, typename ReachedMap>
       
   237   struct DfsIterator {
       
   238     typedef typename Graph::NodeIt NodeIt;
       
   239     Graph& G;
       
   240     std::stack<OutEdgeIt>& bfs_queue;
       
   241     ReachedMap& reached;
       
   242     bool b_node_newly_reached;
       
   243     OutEdgeIt actual_edge;
       
   244     DfsIterator(Graph& _G, 
       
   245 		std::stack<OutEdgeIt>& _bfs_queue, 
       
   246 		ReachedMap& _reached) : 
       
   247       G(_G), bfs_queue(_bfs_queue), reached(_reached) { 
       
   248       actual_edge=bfs_queue.top();
       
   249       if (actual_edge.valid()) { 
       
   250 	NodeIt w=G.bNode(actual_edge);
       
   251 	if (!reached.get(w)) {
       
   252 	  bfs_queue.push(G.firstOutEdge(w));
       
   253 	  reached.set(w, true);
       
   254 	  b_node_newly_reached=true;
       
   255 	} else {
       
   256 	  ++(bfs_queue.top());
       
   257 	  b_node_newly_reached=false;
       
   258 	}
       
   259       } else {
       
   260 	bfs_queue.pop();
       
   261       }
       
   262     }
       
   263     DfsIterator<Graph, OutEdgeIt, ReachedMap>& 
       
   264     operator++() { 
       
   265       actual_edge=bfs_queue.top();
       
   266       if (actual_edge.valid()) { 
       
   267 	NodeIt w=G.bNode(actual_edge);
       
   268 	if (!reached.get(w)) {
       
   269 	  bfs_queue.push(G.firstOutEdge(w));
       
   270 	  reached.set(w, true);
       
   271 	  b_node_newly_reached=true;
       
   272 	} else {
       
   273 	  ++(bfs_queue.top());
       
   274 	  b_node_newly_reached=false;
       
   275 	}
       
   276       } else {
       
   277 	bfs_queue.pop();
       
   278       }
       
   279       return *this;
       
   280     }
       
   281     bool finished() { return bfs_queue.empty(); }
       
   282     operator OutEdgeIt () { return actual_edge; }
       
   283     bool bNodeIsNewlyReached() { return b_node_newly_reached; }
       
   284     bool aNodeIsLeaved() { return !(actual_edge.valid()); }
       
   285   };
       
   286 
       
   287   template <typename Graph, typename OutEdgeIt, typename ReachedMap>
       
   288   struct BfsIterator1 {
       
   289     typedef typename Graph::NodeIt NodeIt;
       
   290     Graph& G;
       
   291     std::queue<OutEdgeIt>& bfs_queue;
       
   292     ReachedMap& reached;
       
   293     bool b_node_newly_reached;
       
   294     OutEdgeIt actual_edge;
       
   295     BfsIterator1(Graph& _G, 
       
   296 		std::queue<OutEdgeIt>& _bfs_queue, 
       
   297 		ReachedMap& _reached) : 
       
   298       G(_G), bfs_queue(_bfs_queue), reached(_reached) { 
       
   299       actual_edge=bfs_queue.front();
       
   300       if (actual_edge.valid()) { 
       
   301       	NodeIt w=G.bNode(actual_edge);
       
   302 	if (!reached.get(w)) {
       
   303 	  bfs_queue.push(OutEdgeIt(G, w));
       
   304 	  reached.set(w, true);
       
   305 	  b_node_newly_reached=true;
       
   306 	} else {
       
   307 	  b_node_newly_reached=false;
       
   308 	}
       
   309       }
       
   310     }
       
   311     void next() { 
       
   312       if (bfs_queue.front().valid()) { 
       
   313 	++(bfs_queue.front());
       
   314 	actual_edge=bfs_queue.front();
       
   315 	if (actual_edge.valid()) {
       
   316 	  NodeIt w=G.bNode(actual_edge);
       
   317 	  if (!reached.get(w)) {
       
   318 	    bfs_queue.push(OutEdgeIt(G, w));
       
   319 	    reached.set(w, true);
       
   320 	    b_node_newly_reached=true;
       
   321 	  } else {
       
   322 	    b_node_newly_reached=false;
       
   323 	  }
       
   324 	}
       
   325       } else {
       
   326 	bfs_queue.pop(); 
       
   327 	actual_edge=bfs_queue.front();
       
   328 	if (actual_edge.valid()) {
       
   329 	  NodeIt w=G.bNode(actual_edge);
       
   330 	  if (!reached.get(w)) {
       
   331 	    bfs_queue.push(OutEdgeIt(G, w));
       
   332 	    reached.set(w, true);
       
   333 	    b_node_newly_reached=true;
       
   334 	  } else {
       
   335 	    b_node_newly_reached=false;
       
   336 	  }
       
   337 	}
       
   338       }
       
   339       //return *this;
       
   340     }
       
   341     bool finished() { return bfs_queue.empty(); }
       
   342     operator OutEdgeIt () { return actual_edge; }
       
   343     bool bNodeIsNewlyReached() { return b_node_newly_reached; }
       
   344     bool aNodeIsExamined() { return !(actual_edge.valid()); }
       
   345   };
       
   346 
       
   347 
       
   348   template <typename Graph, typename OutEdgeIt, typename ReachedMap>
       
   349   struct DfsIterator1 {
       
   350     typedef typename Graph::NodeIt NodeIt;
       
   351     Graph& G;
       
   352     std::stack<OutEdgeIt>& bfs_queue;
       
   353     ReachedMap& reached;
       
   354     bool b_node_newly_reached;
       
   355     OutEdgeIt actual_edge;
       
   356     DfsIterator1(Graph& _G, 
       
   357 		std::stack<OutEdgeIt>& _bfs_queue, 
       
   358 		ReachedMap& _reached) : 
       
   359       G(_G), bfs_queue(_bfs_queue), reached(_reached) { 
       
   360       //actual_edge=bfs_queue.top();
       
   361       //if (actual_edge.valid()) { 
       
   362       //	NodeIt w=G.bNode(actual_edge);
       
   363       //if (!reached.get(w)) {
       
   364       //  bfs_queue.push(OutEdgeIt(G, w));
       
   365       //  reached.set(w, true);
       
   366       //  b_node_newly_reached=true;
       
   367       //} else {
       
   368       //  ++(bfs_queue.top());
       
   369       //  b_node_newly_reached=false;
       
   370       //}
       
   371       //} else {
       
   372       //	bfs_queue.pop();
       
   373       //}
       
   374     }
       
   375     void next() { 
       
   376       actual_edge=bfs_queue.top();
       
   377       if (actual_edge.valid()) { 
       
   378 	NodeIt w=G.bNode(actual_edge);
       
   379 	if (!reached.get(w)) {
       
   380 	  bfs_queue.push(OutEdgeIt(G, w));
       
   381 	  reached.set(w, true);
       
   382 	  b_node_newly_reached=true;
       
   383 	} else {
       
   384 	  ++(bfs_queue.top());
       
   385 	  b_node_newly_reached=false;
       
   386 	}
       
   387       } else {
       
   388 	bfs_queue.pop();
       
   389       }
       
   390       //return *this;
       
   391     }
       
   392     bool finished() { return bfs_queue.empty(); }
       
   393     operator OutEdgeIt () { return actual_edge; }
       
   394     bool bNodeIsNewlyReached() { return b_node_newly_reached; }
       
   395     bool aNodeIsLeaved() { return !(actual_edge.valid()); }
       
   396   };
       
   397 
       
   398 } // namespace marci
       
   399 
       
   400 #endif //MARCI_BFS_HH