// -*- c++ -*-
#include <iostream>
#include <fstream>
#include <list>

#include <hugo/dimacs.h>
#include <bfs_dfs_misc.h>
#include <list_graph.h>

using namespace hugo;

int main() {
  typedef ListGraph Graph;
  Graph g;
  readDimacs(std::cin, g);
  std::list<Graph::Node> l;
  topSort(g, l);
  std::cout << "Leaving order of dfs which is pretopological..." << std::endl;
  for(std::list<Graph::Node>::const_iterator i=l.begin(); i!=l.end(); ++i) {
    std::cout << *i << " ";
  }
  std::cout << std::endl;

  return 0;
}