# 27 + 40 + 2 = 69 dude!
sub num2range {
#234567890123456789012345678901234567890 
my$x=join',',sort{$a-$b}@_; 
$x=~s/\b(\d+)(,((??{$++1})))+\b/$1-$+/g; 
$x 
}