use warnings;
use strict;
use DateTime;

my $year = 2017;
my $dt = DateTime->new(year=>$year)->truncate(to=>'week');
print "_"x24," $year ","_"x24,"\n";
my $dt1 = $dt->clone;
print "Week ";
for (1..7) {
	print "    ",$dt1->day_abbr;
	$dt1->add(days=>1);
}
print "\n";
my $prevmonth=0;
for (1..54) { # weeks
	my $weekno = $dt->week_number;
	printf "%4d ", $weekno;
	my %names;
	for (1..7) { # days in the week
		die unless $dt->week_number==$weekno;
		printf " %3s %02d",
			$prevmonth==$dt->month?'':$dt->month_abbr,
			$dt->day;
		$names{$dt->month_abbr." Week ".($dt->week_of_month+1)}++;
		$prevmonth=$dt->month;
		$dt->add(days=>1);
	}
	print "   (".join(', ',sort keys %names),")\n";
}