static bool missing_line(int k, int i, int[,] grille)
        {
            int n = 0;

            while (n<9)
            {
                if (k == grille[i, n])
                {
                    Console.WriteLine((k == grille[i, n]));
                    return false;
                }
                n++;

            }
            Console.WriteLine(k == grille[i, n]);
            return (k == grille[i, n]);
        }