while(<INPUT>) {
        chomp  $_;
        if ( $_ =~ m#^(\d+)/(\d+)/(\d+)\s+# ) {
                my $date = join( '', ( $3, $1, $2) );
            if ( ! $file_handles{$date} ) {
                open($file_handles{$date}, ">>", "$output_dir/$date") or die "Could not open $date for writing: $!\n";
                print  { $file_handles{$date} } "$_\n";
            }
            elsif ( defined $file_handles{$date} ) {
                print  { $file_handles{$date} } "$_\n";
            }
        }
    }