Task

Write a program or a script that returns the date of the last Fridays of each month of a given year.

The year may be given through any simple input method in your language (command line, std in, etc).



Example of an expected output:

./last_fridays 2012
2012-01-27
2012-02-24
2012-03-30
2012-04-27
2012-05-25
2012-06-29
2012-07-27
2012-08-31
2012-09-28
2012-10-26
2012-11-30
2012-12-28



Related tasks
 Five weekends
 Day of the week
 Find the last Sunday of each month


fridays := proc(year)
	local i, dt, change, last_days;
	last_days := [31,28,31,30,31,30,31,31,30,31,30,31];
	if (Calendar:-IsLeapYear(year)) then
		last_days[2] := 28;
	end if;
	for i to 12 do
		dt := Date(year, i, last_days[i]);
		change := 0;
		if not(Calendar:-DayOfWeek(dt) = 6) then 
			change := -(Calendar:-DayOfWeek(dt) mod 7)-1;
		end if;
		dt := Calendar:-AdjustDateField(dt, "date", change);
		printf("%d-%d-%d\n", year, Month(dt), DayOfMonth(dt));
	end do;
end proc;
 
fridays(2012);