#!/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("$systemNumber");
				while ($totalLength < 4)
				{
					$systemNumber = "0$systemNumber";
					$totalLength = length($systemType) + length("$systemNumber");
				}
				$outputData = "$systemType$systemNumber";
			}
			else
			{
				$outputData .= '_';
			}
		}
		printf "%-4s -> %s\n", $inputData, $outputData;
	}
}

exit;

__END__