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.
Simply type make chez
if you're using ChezScheme or make guile
if you're using GNU Guile.
Sometimes the name for the scheme binary on your system will differ from the defaults.
When this is the case, you'll need to tell make by running make chez chez=your-chez-binary
or make guile guile=your-guile-binary
.
(load "test.scm")
at the repl prompt.leap.scm
reloading as you go.(test)
to check your solution.If some of the test cases fail, you should see the failing input and the expected output.
The failing input is presented as a list because the tests call your solution by (apply leap input-list)
.
To learn more about apply
see The Scheme Programming Language -- Chapter 5
Sign up to Exercism to learn and master Scheme with 39 exercises, and real human mentoring, all for free.