#include <iostream>
 
#include <boost/graph/adjacency_list.hpp>
#include <boost/range/iterator_range.hpp>
 
using std::cout;
 
int main() {
  boost::adjacency_list<boost::vecS, boost::vecS, boost::undirectedS> g;
 
  add_edge(0, 1, g);
  add_edge(1, 2, g);
 
  for(auto v : make_iterator_range(vertices(g))) {
    cout << v << " has " << degree(v, g) << " neighbor(s): ";
    for(auto w : make_iterator_range(adjacent_vertices(v, g))) cout << w << ' ';
    cout << '\n';
  }
  return 0;
}
 

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