use strict;

my $a="123-135, 111-119, 127-130, 140-145";
print "Original : $a\n";

my @a = split (/\, /, $a);
eval{s/^(\d{2})(\d+)\-(\d{2})(\d+)$/&digit($1,$2,$3,$4)/egsi;} for (@a);

print "Changed  : ";
print "$_\t" for @a;

sub digit{
	my ($f, $f1, $s, $s1)=@_; 	
	if ($f == $s){
		$s=$s1;
	}
	else{
		$s=~s/\d//; $s.=$s1;
	}		
return qq($f$f1-$s);
}