use strict;
use warnings;
# use GraphViz;
use CGI;
use IPC::Run qw(run binary);

my $q = new CGI();
print $q->header(), $q->start_html();

my $dot = qq(digraph g { graph [] A -> B; C -> B; });
run ['dot', '-Tgif'], \$dot, '>', binary(), 'test_tree.gif';

print $q->end_html;