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\begin{verbatim}
#include<LINK/basic/Sequence.h>
#include<LINK/graph/DBinGraph.h>
#include<LINK/graph/Attribute.h>
#include<LINK/algorithm/Algorithms.h>

main()
{
        DBinGraph g;
        Sequence<Vertex*>  s, postorder;
        Vertex *parent, *child1, *child2;

        child1 = g.addVertex("child1"); 
        parent = g.addVertex("parent");
        child2 = g.addVertex("child2");
        s.insert(parent); s.append(child1);  
        g.addEdge(s);
        s.clear();
        s.insert(parent); s.append(child2);  
        g.addEdge(s);
        
        postorder = DFS(&g);
        cout << postorder << endl;
}
\end{verbatim}

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\begin{verbatim} 
<child1 child2 parent>
\end{verbatim}

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