$filein = "sample.txt";
open(FILE, $filein) or die "Couldn't open file $file";

while (<FILE>) {
	$line = $_;
	(@values) = split ( /(,)/ , $line);
	
	foreach $value(@values) {
		if ($value =~ /-\d{2}/) {$value =~ s/-/0/}
		elsif ($value =~ /-\d{3}/) {$value =~ s/-//}
	}
	push (@newfile,@values);
	print @values;
}
$filein=~ s/.txt/.tst/;
open (NEW, ">$filein");
print NEW "@newfile";
close (NEW);