perl localtime 時間隔式計算

perl 使用 localtime 來算出現在系統時間，

底下作一個 func_date_time function

再拿一個值給 func_date_time 讓它顯示秒、分、時、日、月、年、週

use strict;
sub func_date_time {
        my ($date_second,$date_minute,$date_hour,$date_day,$date_month,$date_year,$date_week)=localtime(time);
        $date_month++;
        $date_year+=1900;

        if (length($date_second) == 1) {$date_second = "0"."$date_second";}
        if (length($date_minute) == 1) {$date_minute = "0"."$date_minute";}
        if (length($date_hour) == 1) {$date_hour = "0"."$date_hour";}
        if (length($date_day) == 1) {$date_day = "0"."$date_day";}
        if (length($date_month) == 1) {$date_month = "0"."$date_month";}

        my $which_time = shift;

        if ($which_time) {

          if ($which_time =~ /second/) {
                  return $date_second;
          } elsif ($which_time =~ /minute/){
                  return $date_minute;
          } elsif ($which_time =~ /hour/){
                  return $date_hour;
          } elsif ($which_time =~ /day/){
                  return $date_day;
          } elsif ($which_time =~ /month/){
                  return $date_month;
          } elsif ($which_time =~ /year/){
                  return $date_year;
          } elsif ($which_time =~ /week/){
                  return $date_week;

          }

        } else {
                  return "$date_year/$date_month/$date_day $date_hour:$date_minute:$date_second";
        }
}

print my $sec = func_date_time('second');
print " ";
print my $min = func_date_time('minute');
print " ";
print my $hr = func_date_time('hour');
print " ";
print my $day = func_date_time('day');
print " ";
print my $month = func_date_time('month');
print " ";
print my $year = func_date_time('year');
print " ";
print my $week = func_date_time('week');