a b c
0 0 d
0 1 d
0 1 d
0 2 d
0 2 d
1 0 d
1 0 d
1 1 d
1 1 d
1 2 d
1 2 d 

##</code><code>##

a b c	a b c	
0 0 d	1 0 d
0 1 d	1 0 d
0 1 d	1 1 d
0 2 d	1 2 d
0 2 d	1 2 d 

##</code><code>##

foreach my $va (sort {$a <=> $b} keys %myhash) {
       	foreach my $vb (sort {$a <=> $b} keys %{ $myhash{$va} }) {
		       	my $vc = $myhash{$va}{$vb};
				print OUTFILE "$va\t$vb\t$vc\n";
			}
		}
}