Last Friday of each month: Difference between revisions

=={{header|COBOL}}==

<lang COBOL>

program-id. last-fri.

data division.

working-storage section.

1 wk-date.

2 yr pic 9999.

2 mo pic 99 value 1.

2 da pic 99 value 1.

1 rd-date redefines wk-date pic 9(8).

1 binary.

2 int-date pic 9(8).

2 dow pic 9(4).

2 friday pic 9(4) value 5.

procedure division.

display "Enter a calendar year (1601 thru 9999): "

with no advancing

accept yr

if yr >= 1601 and <= 9999

continue

else

display "Invalid year"

stop run

end-if

perform 12 times

move 1 to da

add 1 to mo

if mo > 12 *> to avoid y10k in 9999

move 12 to mo

move 31 to da

end-if

compute int-date = function

integer-of-date (rd-date)

if mo =12 and da = 31 *> to avoid y10k in 9999

continue

else

subtract 1 from int-date

end-if

compute rd-date = function

date-of-integer (int-date)

compute dow = function mod

((int-date - 1) 7) + 1

compute dow = function mod ((dow - friday) 7)

subtract dow from da

display yr "-" mo "-" da

add 1 to mo

end-perform

stop run

.

end program last-fri.

</lang>

{{out}}

<pre>

2016-01-29

2016-02-26

2016-03-25

2016-04-29

2016-05-27

2016-06-24

2016-07-29

2016-08-26

2016-09-30

2016-10-28

2016-11-25

2016-12-30

</pre>