public static int getTotalX(List a, List b) {

    int counter = 0;
    if (a.Count>=1 && a.Count <= 10 && b.Count>=1 && b.Count <= 10)
    {
        int max1 = a.Max(x => x);
        int max2 = b.Max(x => x);
        int min1 = a.Min(x => x);
        int min2 = b.Min(x => x);
        int MaxCondition = max1 > max2 ? max1 : max2;
        int minCondition = min1 > min2 ? min2 : min1;


        for (int i = minCondition; i <=MaxCondition && i<=100; i++)
        {
            if (a.All(x => i % x == 0) && b.All(y => y % i == 0))
            {
                counter++;

            }
        }
    }
    return counter;
}