sub date
{
  my ($date) = @_;
  my ($y, $m, $d);
  ($y,$m,$d) = ($date =~ /^(\d{4})(\d{2})(\d{2})$/)   
    or
  ($y,$m,$d) = ($date =~ /^(\d{4})-(\d{1,2})-(\d{1,2})$/)   
    or
  ($d,$m,$y) = ($date =~ /^(\d{1,2})\.(\d{1,2})\.(\d{4})$/) 
    or
  ($m,$d,$y) =  ($date =~ m#^(\d{1,2})/(\d{1,2})/(\d{4})$#)  
    or
  fehler "falsches Format";
  return timegm(0,0,0, $d,$m-1,$y-1900);
}