use strict;
use warnings;

my $cutoff = 30;

print
   map  { $_->[0] }
   sort {
            $a->[3] cmp $b->[3]
            ||
            $a->[1] cmp $b->[1]
            ||
            $a->[2] cmp $b->[2]
        }
   map  { $_->[3] += $_->[3] >= $cutoff ? 1900 : 2000; $_ }
   map  { [ $_, m{(\d\d)/(\d\d)/(\d\d)} ] }
   <DATA>;


__END__
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09/06/04
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10/17/98
04/24/99

##</code><code>##

10/17/98
04/24/99
06/24/99
12/03/99
12/24/99
09/06/04