PWC 227
PWC 227 Challenge 1 (Friday 13th) This challenge requires us to count the number of times Friday 13th occurs in a particular year. I use Date::Manip. This module probably has easier ways to do this using a Date Range, but my approach is easy enough. My &friday_13th subroutine takes the year as input, throws an exception if it is outside the specified range (1753 to 9999), and then cycles through the 13th of each month, counting the Fridays. use Date::Manip; my $dateobj=Date::Manip::Date->new(); sub friday_13th { my ($year)=@_; my $retval=0; ( ($year > 9999) || ($year < 1753) ) && die "Year should be between 1753 and 9999"; map { ( ($dateobj->new_date("$year-$_-13")->printf('%w') ) == 5 ) && $retval++; } ...