// -*- c++ -*-

 #include <iostream>

 #include <fstream>

 #include <sage_graph.h>

 //#include <smart_graph.h>

 #include <lemon/dimacs.h>

 #include <lemon/time_measure.h>

 #include <lemon/for_each_macros.h>

 #include <bfs_dfs.h>

 using namespace lemon;

 int main() {

   typedef SageGraph Graph; 

   typedef Graph::Node Node;

   typedef Graph::NodeIt NodeIt;

   typedef Graph::Edge Edge;

   typedef Graph::EdgeIt EdgeIt;

   typedef Graph::OutEdgeIt OutEdgeIt;

   Graph g;

   Node s, t;

   Graph::EdgeMap<int> cap(g);

   //readDimacsMaxFlow(std::cin, g, s, t, cap);

   readDimacs(std::cin, g);

   Graph::NodeMap<OutEdgeIt> pred(g);

   Timer ts;

   /*

   {

     ts.reset();

     Graph::NodeMap<bool> reached(g);

     reached.set(s, true);

     pred.set(s, INVALID);

     std::queue<Node> bfs_queue;

     bfs_queue.push(t);

     while (!bfs_queue.empty()) {

       Node v=bfs_queue.front();	

       bfs_queue.pop();

       OutEdgeIt e;

       for(g.first(e,v); g.valid(e); g.next(e)) {

 	Node w=g.target(e);

 	if (!reached[w]) {

 	  bfs_queue.push(w);

 	  reached.set(w, true);

 	  pred.set(w, e);

 	}

       }

     }

     std::cout << ts << std::endl;

   }

   */

   {

     ts.reset();

     Graph::NodeMap<bool> bfs_reached(g);

     Graph::NodeMap<Edge> bfs_pred(g); 

     Graph::NodeMap<int> bfs_dist(g);

     Bfs< Graph, Graph::NodeMap<bool>, 

       Graph::NodeMap<Edge>, Graph::NodeMap<int> > 

       bfs(g,bfs_reached, bfs_pred, bfs_dist );

     bfs.run(s);

     /*

     pred.set(s, INVALID);

     while (!bfs.finished()) { 

       ++bfs; 

       if (g.valid(bfs) && bfs.isBNodeNewlyReached()) 

 	pred.set(bfs.bNode(), bfs);

     }

     */

     std::cout << ts << std::endl;

   }

   return 0;

 }