my $input = <main::DATA>;
my $d = 0;
$_ = $input;
s/\s(\d+)\/(\d+)\/(\d{4})\s/{$d = 10000*$3+100*$1+$2 if $d < 10000*$3+100*$1+$2}/eg;
__DATA__
File:tfo.supplement.20120901.done 9/1/2012 3:48:00 AM
File:tfo.supplement.20120901.zip 421144 KB 9/1/2012 3:48:00 AM
File:tfo.supplement.20120904.done 9/4/2012 3:57:00 AM
File:tfo.supplement.20120904.zip 421794 KB 9/4/2012 3:57:00 AM
File:tfo.supplement.20120905.done 9/5/2012 3:28:00 AM
File:tfo.supplement.20120905.zip 421875 KB 9/5/2012 3:28:00 AM
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