#!/usr/bin/perl -w

use strict;

my    @TestData =
(
    'a',
    'NTX',
    'NT8',
    'NT9',
    'NT10',
    'NT11',
);


{
    foreach my $inputData (@TestData)
    {
        my $outputData = $inputData;
        while (length($outputData) < 4)
        {
            if ($outputData =~ /^(\D*)(\d+)$/)
            {
                my $systemType = $1;
                my $systemNumber = $2;
                my $totalLength = length($systemType) + length("$syste
+mNumber");
                while ($totalLength < 4)
                {
                    $systemNumber = "0$systemNumber";
                    $totalLength = length($systemType) + length("$syst
+emNumber");
                }
                $outputData = "$systemType$systemNumber";
            }
            else
            {
                $outputData .= '_';
            }
        }
        printf "%-4s -> %s\n", $inputData, $outputData;
    }
}

exit;

__END__
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