using System;

using System.Linq;

​

class Program

{

    static void Main()

    {

        DateRangeEvaluator validator = new(new(2024, 12, 1), new(2025, 2, 1));

        DateOnly startDate = new(1900, 10, 1);

        foreach (var date in Enumerable.Range(0, 6).Select(startDate.AddMonths))

        {

            bool isInBetween = validator.IsBetween(date);

            Console.WriteLine($"Date: {date} between {validator.MinDate} and {validator.MaxDate}: {isInBetween}");

        }

    }

}

​

public class DateRangeEvaluator

{

    public DateRangeEvaluator(DateOnly minDate, DateOnly maxDate)

    {

        if (minDate > maxDate) throw new ArgumentException("MinDate must not be greater than MaxDate");

        MinDate = minDate;

        MaxDate = maxDate;

    }

​

    public DateOnly MinDate { get; }

    public DateOnly MaxDate { get; }

​

    public bool IsBetween(DateOnly checkDate)

    {

        if (MinDate.Year != MaxDate.Year)

        {

            bool checkMaxDate = checkDate.Month < MinDate.Month;

            int newCheckDateYear = checkMaxDate ? MaxDate.Year : MinDate.Year;

            checkDate = new(newCheckDateYear, checkDate.Month, checkDate.Day);

            return checkMaxDate ? checkDate <= MaxDate : checkDate >= MinDate;

        }

​

        DateOnly compareDateMin = new(checkDate.Year, MinDate.Month, MinDate.Day);

        DateOnly compareDateMax = new(checkDate.Year, MaxDate.Month, MaxDate.Day);

        return checkDate >= compareDateMin && checkDate <= compareDateMax;

    }

}