# Leap Given a year, report if it is a leap year. The tricky thing here is that a leap year in the Gregorian calendar occurs: ```text 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. If your language provides a method in the standard library that does this look-up, pretend it doesn't exist and implement it yourself. ## Notes 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][video]. [video]: http://www.youtube.com/watch?v=xX96xng7sAE * * * * For installation and learning resources, refer to the [exercism Racket page](http://exercism.io/languages/racket). You can run the provided tests through DrRacket, or via the command line. To run the test through DrRacket, simply open the test file and click the 'Run' button in the upper right. To run the test from the command line, run the test from the exercise directory with the following command: ``` raco test leap-test.rkt ``` which will display the following: ``` raco test: (submod "leap-test.rkt" test) 2 success(es) 0 failure(s) 0 error(s) 2 test(s) run 0 2 tests passed ``` ## Source JavaRanch Cattle Drive, exercise 3 [http://www.javaranch.com/leap.jsp](http://www.javaranch.com/leap.jsp) ## Submitting Incomplete Solutions It's possible to submit an incomplete solution so you can see how others have completed the exercise.