print "Content-type: text/plain\n\n";
print "A week ago the date was ",date_a_week_ago(),"\n";
  
# return a date one week ago as a string in format: MM/DD/YYYY
sub date_a_week_ago {

    my @month_len = (31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31);
    my($day, $month, $year) = (localtime)[3..5];

    for (my $j = 0; $j < 7; $j++) {

        $day--;
        if ($day == 0) {

            $month--;
            if ($month == 0) {
                $year--;
                $month = 12;
            }

            # there are 29 days in February in a leap year
            $month_len[1] =  
                ($year % 400 == 0 or ($year % 4 == 0 and $year % 100))
                    ? 29 : 28;

            # set $day to be the last day of the previous month 
            $day = $month_len[$month - 1]; 
        }
    }

    return sprintf "%02d/%02d/%04d", $month, $day, $year+1900;
}