use Graph::Directed;
use warnings;
use strict;

# Instantiate
my $G = new Graph::Directed;
my @V = ();

# Create graph
$G = $G->add_edge("E1", "E2");
$G = $G->add_edge("E3", "E3");
$G = $G->add_edge("E3", "E2");
$G = $G->add_edge("E3", "E1");
$G = $G->add_edge("E2", "E2");
$G = $G->add_edge("E2", "E2");
$G = $G->add_edge("E2", "E2");
$G = $G->add_edge("E3", "E3");
$G = $G->add_edge("E3", "E3");

# Print some info about graph
print $G, "\n";