#!/usr/bin/perl -w
use strict;
use warnings;
use diagnostics;
use Graph;
use Graph::Traversal::DFS;


my $g = Graph->new();
$graph->add_edges ( ['A', 'B'], ['B', 'C'], ['C', 'D'], ['D', 'K'], ['
+D', 'Z'], ['K', 'R'] );

=some

Path 1: 
A -> B -> C -> D -> K -> R

Path 2:
A -> B -> C -> D -> Z

=cut

my $t = Graph::Traversal::DFS->new($g);
my @v = $t->preorder;
print qq[Preorder:\n];
print qq[$_\t] foreach @v;
print qq[\n];
@v = $t->postorder;
print qq[Postorder:\n];
print qq[$_\t] foreach @v;
print qq[\n];
my @r = $t->roots;
print qq[Roots:\n];
print qq[$_\t] foreach @r;
print qq[\n];
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