#!/usr/bin/perl -w
use strict;

use Math::Roman qw(roman);
my $roman = new Math::Roman;

$\ = "\n";

while (<DATA>) {
	chomp;
	my $old_name = $_;

	if ($old_name =~ /^(.+\d{6})(\w+)?(\.htm)$/) {
		my $old_roman = $2 || 1; 
		my $new_roman = roman("$old_roman") + 1;
		my $new_name = $1 . $new_roman . $3;
		print "$old_name => $new_name";
	}
}

__DATA__
filename230804.htm
filename230804IV.htm
filename230804V.htm
filename230804II.htm
filename230804X.htm

##</code><code>##

filename230804.htm => filename230804II.htm
filename230804IV.htm => filename230804V.htm
filename230804V.htm => filename230804VI.htm
filename230804II.htm => filename230804III.htm
filename230804X.htm => filename230804XI.htm