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\begin{verbatim}
#include<iostream.h>
#include<LINK/graph/DBinGraph.h>
#include<LINK/graph/Vertex.h>
#include<LINK/graph/Attribute.h>

void main()
{
        DBinGraph g1;
        if (newAttribute((Graph*)&g1, "test_attr", 1) != LINK_OK)
                error("Attr.cc: error creating test_attr");

        g1.addVertices(4);
        Vertex** vertices = g1.vertexStart();
        int num_vertices = g1.order();

        for (int i=2; i<num_vertices; i++) {
                setAttribute((GraphObject*)vertices[i], "test_attr", i);
        }
        int value;
        for (i=0; i<num_vertices; i++) {
                getAttribute((GraphObject*)vertices[i], "test_attr", value);
                cout << "v: "<<*vertices[i]<<" test_attr: "<<value<<endl;
        }
}
\end{verbatim}

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\begin{verbatim} 
v: 0 test_attr: 1
v: 1 test_attr: 1
v: 2 test_attr: 2
v: 3 test_attr: 3
\end{verbatim}

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