#include <iostream>
#include <boost/graph/adjacency_list.hpp>

using namespace boost;
using namespace std;

typedef adjacency_list<listS, // change to multisetS to make it work
                       listS, bidirectionalS> Graph;               
               
int main()
{
    Graph g;
    
    graph_traits<Graph>::vertex_descriptor v[4];
   
    for (int i = 0; i < 4; ++i)
        v[i] = add_vertex(g);

    add_edge(v[0],v[1],g);
    add_edge(v[1],v[2],g);
    add_edge(v[2],v[0],g);
    add_edge(v[0],v[3],g);

    // add parallel edge
    graph_traits<Graph>::edge_descriptor e;
    e = add_edge(v[0],v[1],g).first;

    cout << "number of edges before removal: " << num_edges(g) << endl; 
    remove_edge(e,g);
    cout << "number of edges after removal: " << num_edges(g) << endl;
    
    return 0;   
}