// C# Extension Method

// Doc: https://csharp-extension.com/en/method/1002400/int32-isleapyear

​

// @nuget: Z.ExtensionMethods

​

using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Leap years between 1990 and 2020.\n\n");

        for (int year = 1990; year <= 2020; year++)

        {

            // C# Extension Method: Int32 - IsLeapYear

            if (DateTime.IsLeapYear(year))

            {

                Console.WriteLine(year);

            }

        }

    }

}