One way: 
use strict;
use warnings;
use Time::Piece;

my $month = 11;
my $t = Time::Piece->strptime($month, '%m');
my $last_day_month = $t->month_last_day();
print "$last_day_month\n";

__END__

30

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To account for leap years, you may need to also specify the year.

In reply to Re: Given month last day by toolic
in thread Given month last day by Anonymous Monk

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