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to Leap in the C# Track

Published at Sep 29 2020 · 0 comments
Instructions
Test suite
Solution

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.

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.

Notes

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.

Source

JavaRanch Cattle Drive, exercise 3 http://www.javaranch.com/leap.jsp

LeapTests.cs

// This file was auto-generated based on version 1.6.0 of the canonical data.

using Xunit;

public class LeapTests
{
    [Fact]
    public void Year_not_divisible_by_4_in_common_year()
    {
        Assert.False(Leap.IsLeapYear(2015));
    }

    [Fact(Skip = "Remove this Skip property to run this test")]
    public void Year_divisible_by_2_not_divisible_by_4_in_common_year()
    {
        Assert.False(Leap.IsLeapYear(1970));
    }

    [Fact(Skip = "Remove this Skip property to run this test")]
    public void Year_divisible_by_4_not_divisible_by_100_in_leap_year()
    {
        Assert.True(Leap.IsLeapYear(1996));
    }

    [Fact(Skip = "Remove this Skip property to run this test")]
    public void Year_divisible_by_4_and_5_is_still_a_leap_year()
    {
        Assert.True(Leap.IsLeapYear(1960));
    }

    [Fact(Skip = "Remove this Skip property to run this test")]
    public void Year_divisible_by_100_not_divisible_by_400_in_common_year()
    {
        Assert.False(Leap.IsLeapYear(2100));
    }

    [Fact(Skip = "Remove this Skip property to run this test")]
    public void Year_divisible_by_100_but_not_by_3_is_still_not_a_leap_year()
    {
        Assert.False(Leap.IsLeapYear(1900));
    }

    [Fact(Skip = "Remove this Skip property to run this test")]
    public void Year_divisible_by_400_in_leap_year()
    {
        Assert.True(Leap.IsLeapYear(2000));
    }

    [Fact(Skip = "Remove this Skip property to run this test")]
    public void Year_divisible_by_400_but_not_by_125_is_still_a_leap_year()
    {
        Assert.True(Leap.IsLeapYear(2400));
    }

    [Fact(Skip = "Remove this Skip property to run this test")]
    public void Year_divisible_by_200_not_divisible_by_400_in_common_year()
    {
        Assert.False(Leap.IsLeapYear(1800));
    }
}
using System;

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

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