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

# Instantiate
my $G = new Graph::Directed;

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

# Weight edges (constant)
$G->set_attribute("weight", "E1", "E2", 1);
$G->set_attribute("weight", "E2", "E3", 1);
$G->set_attribute("weight", "E3", "E1", 1);
$G->set_attribute("weight", "E3", "E2", 1);
$G->set_attribute("weight", "E2", "E2", 1);
$G->set_attribute("weight", "E3", "E3", 1);

# Give meaningful names to edges
$G->set_attribute("name", "E1", "E2", "C");
$G->set_attribute("name", "E2", "E3", "F");
$G->set_attribute("name", "E3", "E1", "A");
$G->set_attribute("name", "E3", "E2", "F");
$G->set_attribute("name", "E2", "E2", "C,E,F");
$G->set_attribute("name", "E3", "E3", "A,F");

# Print some info about graph
print "GRAPH (", scalar $G->vertices, " vertices):\n", $G, "\n\n";

# All Pairs Shortest Path
my $APSP = $G->APSP_Floyd_Warshall;
print "ALL AVAILABLE PAIRS:\n", $APSP, "\n\n";

print "DISTANCE MATRIX:\n";
print "\t", join ("\t", $G->vertices), "\n";
foreach my $rowVtx ($G->vertices) {
    print "$rowVtx\t";
    foreach my $colVtx ($G->vertices) {
	$APSP->get_attribute("weight", $rowVtx, $colVtx);
	print $APSP->get_attribute("weight", $rowVtx, $colVtx), "\t";
    }
    print "\n";
}

##</code><code>##

GRAPH (3 vertices):
E1-E2,E2-E2,E2-E3,E3-E1,E3-E2,E3-E3

ALL AVAILABLE PAIRS:
E1-E1,E1-E2,E1-E3,E2-E1,E2-E2,E2-E3,E3-E1,E3-E2,E3-E3

DISTANCE MATRIX:
        E1      E2      E3
E1      0       1       2
E2      2       0       1
E3      1       1       0

##</code><code>##

DISTANCE MATRIX:
        E1      E2      E3
E1      3       1       2
E2      2       1       1
E3      1       1       1