$ perl -e '
> my @list = qw/12112014
> 01052015
> 02202015
> 03102015
> 01012011
> 10102014
> 04092015
> 09092015
> 09092013/;
> chomp @list;
> my $max_y = "0000";
> my $max_d = "0000";
> for my $dir  (@list) {
>      my ($d, $y) = $dir =~ /(\d{4})(\d{4})/;
>      if ($y > $max_y) {
>          $max_y = $y;
>      } elsif ($y == $max_y) {
>          $max_d = $d if $d > $max_d;
>     }
> }
> print "$max_d$max_y\n";
> '
09092015