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\begin{verbatim}
#include<iostream.h>
#include<LINK/basic/DList.h>

main()
{
        DList<int> l;

        ContainerNode *cn = l.insert(3);
        l.insertBefore(4, cn);
        cout << l << endl;

        cout << "value: " << l.info(l.predecessor(cn)) << endl; 
}
\end{verbatim}

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\begin{verbatim} 
(4 3)
value: 4
\end{verbatim}

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