static void Main(string[] args)
        {
            Console.WriteLine("请输入一个字符串，将会反序输出：");
            string words = Console.ReadLine();
            char[] strchar = words.ToCharArray();
            for (int index = strchar.Length - 1; index >= 0; index--)
            {
                Console.Write(strchar[index]);
            }
            Console.ReadLine();
        }