use Date::Calc qw( Decode_Date_EU Today leap_year Delta_Days );
  $date = <STDIN>; # get birthday
  ($year1,$month1,$day1) = Decode_Date_EU($date);
  ($year2,$month2,$day2) = Today();
  if (($day1 == 29) && ($month1 == 2) && !leap_year($year2))
      { $day1--; }
  if ( (($year2 - $year1) >  18) ||
     ( (($year2 - $year1) == 18) &&
     (Delta_Days($year2,$month1,$day1, $year2,$month2,$day2) >= 0) ) )
  {
      print "Ok - you are over 18.\n";
  }
  else
  {
      print "Sorry - you aren't 18 yet!\n";
  }