template parameters, though here we only fill in the first three parameters and
use the defaults for the remaining three. The first two template arguments (<tt>vecS,
vecS</tt>) determine the data structure used to represent the out-edges for each
vertex in the graph and the data structure used to represent the graph's vertex
set (see section <a href="using_adjacency_list.html#sec:choosing-graph-type">Choosing
the <tt>Edgelist</tt> and <tt>VertexList</tt></a> for information about the
tradeoffs of the differ