using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine(CheckACArticleNo("000000"));

    }

    public static bool CheckACArticleNo(string articleNumber)

    {

        var checkValue = articleNumber.Trim();

        var isANumber = int.TryParse(checkValue, out var numericArticle);

        if (isANumber && (checkValue.Length == 10 || checkValue.Length == 8)) {

            return true;

        }

        if (!isANumber && checkValue.Length <= 7) {

            return true;    

        }

        if(checkValue.Length <= 25) {

            return false;   

        }

        return true;

    }

}