public static bool checkLetter(string input1, string input2)
        {
            int x = 0;
            int z = 0;
            if (input1 == string.Empty || input2 == string.Empty)
            {
                return false;
            }
            while (true)
            {
                if (z < input2.Length)
                {
                    z++;
                    if (z >= input2.Length)
                    {
                        z = 0;
                        x++;
                        if (x >= input1.Length)
                            return false;
                    }
                }

                if (input1[x] == input2[z])
                    return true;
            }
        }