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artemkorsakov's solution

to Leap in the C# Track

Published at Feb 05 2019 · 0 comments
Test suite


This exercise has changed since this solution was written.

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.

If your language provides a method in the standard library that does this look-up, pretend it doesn't exist and implement it yourself.


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.


The DateTime class in C# provides a built-in IsLeapYear method which you should pretend doesn't exist for the purposes of implementing this exercise.

Running the tests

To run the tests, run the command dotnet test from within the exercise directory.

Initially, only the first test will be enabled. This is to encourage you to solve the exercise one step at a time. Once you get the first test passing, remove the Skip property from the next test and work on getting that test passing. Once none of the tests are skipped and they are all passing, you can submit your solution using exercism submit Leap.cs

Further information

For more detailed information about the C# track, including how to get help if you're having trouble, please visit the exercism.io C# language page.


JavaRanch Cattle Drive, exercise 3 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.


// This file was auto-generated based on version 1.4.0 of the canonical data.

using Xunit;

public class LeapTest
    public void Year_not_divisible_by_4_is_common_year()

    [Fact(Skip = "Remove to run test")]
    public void Year_divisible_by_4_not_divisible_by_100_is_leap_year()

    [Fact(Skip = "Remove to run test")]
    public void Year_divisible_by_100_not_divisible_by_400_is_common_year()

    [Fact(Skip = "Remove to run test")]
    public void Year_divisible_by_400_is_leap_year()

    [Fact(Skip = "Remove to run test")]
    public void Year_divisible_by_200_not_divisible_by_400_is_common_year()
using System;

public static class Leap
    public static bool IsLeapYear(int year)
        return year % 400 == 0 || (year % 100 != 0 && year % 4 == 0);

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