use strict;
use warnings;

my ($i, $j, $k, $p1, $p2, $p3, $val, %hash);

for $i (0..2) {
    for $j (3..5) {
        for $k (qw/first second third/) {
            $hash{$i}{$j}{$k} = "$i $j $k";
        }
    }
}

$p1 = \%hash;
for $i (sort {$a <=> $b} keys %$p1) {
    $p2 = $p1->{$i};
    for $j (sort {$a <=> $b} keys %$p2) {
        $p3 = $p2->{$j};
        for $k (sort keys %$p3) {
            $val = $p3->{$k};
            print "\$hash{$i}{$j}{$k} = '$val';\n";
        }
    }
}