# Checkt das Datum 
sub check_date{
 return 0 if scalar @_ != 3;
 my ($day, $month, $year) = @_;
 my $zahl = "$day$month$year";
 if($zahl =~ /[^0-9]/){return 0}
 if($month > 12 or $month <= 0 or $day <= 0 and $year < 1582){return 0}
 if($day > &days_of_month($month,$year)){return 0}
 if($month < 10 and $year < 1582){return 0} # 15.10.1582 Gregorian Day
 # over!
 return 1;
}