my @sorted= Filter {
       s#\d{2}(\d+)#\1#g
   } sort Filter {
       s#(\d+)# sprintf "%02d%s", length($1), $1 #g
   } @data;

##</code><code>##

    my @data = qw/a.1 a.5 a.11 b.3 b.15/;

##</code><code>##

use Algorithm::Loops (MapCarE);

my $dateTime= join "", MapCarE {
    sprintf "%02d%s", pop()+pop(), pop()
} [ (localtime)[5,4,3,2,1,0] ],
  [ 1900, 1, (0)x4 ],
  [ "// ::" =~ /./g, "" ];

print $dateTime,$/;
print scalar localtime(),$/; ## for a more familiar view

__OUTPUT__
1900103018003000100130037
Tue Sep 30 01:13:37 2003