Given a year, report if it is a leap year.
The tricky thing here is that a leap year in the Gregorian calendar occurs:
on every year that is evenly divisible by 4
except every year that is evenly divisible by 100
unless the year is also evenly divisible by 400
For example, 1997 is not a leap year, but 1996 is. 1900 is not a leap year, but 2000 is.
Though our exercise adopts some very simple rules, there is more to learn!
For a delightful, four minute explanation of the whole leap year phenomenon, go watch this youtube video.
For library documentation, follow Useful OCaml resources.
A Makefile
is provided with a default target to compile your solution and run the tests. At the command line, type:
make
It's possible to submit an incomplete solution so you can see how others have completed the exercise.
The exercism/ocaml repository on GitHub is the home for all of the Ocaml exercises.
If you have feedback about an exercise, or want to help implementing a new one, head over there and create an issue or submit a PR. We welcome new contributors!
JavaRanch Cattle Drive, exercise 3 http://www.javaranch.com/leap.jsp
(* leap - 1.5.1 *)
open OUnit2
open Leap
let ae exp got _test_ctxt = assert_equal exp got ~printer:string_of_bool
let tests = [
"year not divisible by 4 in common year" >::
ae false (leap_year 2015);
"year divisible by 2, not divisible by 4 in common year" >::
ae false (leap_year 1970);
"year divisible by 4, not divisible by 100 in leap year" >::
ae true (leap_year 1996);
"year divisible by 100, not divisible by 400 in common year" >::
ae false (leap_year 2100);
"year divisible by 400 in leap year" >::
ae true (leap_year 2000);
"year divisible by 200, not divisible by 400 in common year" >::
ae false (leap_year 1800);
]
let () =
run_test_tt_main ("leap tests" >::: tests)
let leap_year year =
let divisible_by n = year mod n = 0 in
divisible_by 4 && (not (divisible_by 100) || divisible_by 400)
A huge amount can be learned from reading other peopleโs code. This is why we wanted to give exercism users the option of making their solutions public.
Here are some questions to help you reflect on this solution and learn the most from it.
Level up your programming skills with 3,450 exercises across 52 languages, and insightful discussion with our volunteer team of welcoming mentors. Exercism is 100% free forever.
Sign up Learn More
Community comments