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\begin{verbatim}
#include<iostream.h>
#include<LINK/graph/UBinGraph.h>
#include<LINK/graph/DBinGraph.h>
#include<LINK/basic/Sequence.h>


main()
{
        UBinGraph ug;
        DBinGraph dg;
        Sequence<Vertex*> sq;
        Set<Vertex*>       s;
        Vertex *v1, *v2;

        v1 = ug.addVertex("v1");
        v2 = ug.addVertex("v2");
        s.append(v2); s.append(v1);   // must obey sorted order
        ug.addEdge(s);
        cout << ug << endl;
        
        v1 = dg.addVertex("v1");
        v2 = dg.addVertex("v2");
        sq.append(v2); sq.append(v1);
        dg.addEdge(sq); 
        cout << dg << endl;
}
\end{verbatim}

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\begin{verbatim} 
{[v1 v2]  {{v1 v2}}}
{[v1 v2]  {<v2 v1>}}
\end{verbatim}

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