()</TT>. The <TT>get()</TT>
function takes a property map object, such as <TT>distance</TT> and
a <I>key</I> object. In the case of the distance property we are using
the vertex objects <TT>u</TT> and <TT>v</TT> as keys. The <TT>get()</TT>
function then returns the property value for the vertex.

<P>
<PRE>
  template &lt;class Edge, class Graph,
            class WeightPropertyMap, 
            class DistancePropertyMap&gt;
  bool relax(Edge e, const Graph&amp; g, 
             WeightPropertyMap weight, 
  