C# Leapyear
using System;
public static class Leap
{
    public static bool IsLeapYear(int year)
    {
        if(year % 4 == 0 && year % 100 == 0 && year % 400 == 0)
            return true;
        else if (year % 4 == 0 && year % 100 == 0)
            return false;
        else if (year % 4 == 0)
            return true;
        else
            return false;
    }
}
