双向链表的应用 26个英文字母 任意输入一个整数，能够实现以下功能：例如输入3, 输出结果为：DEFGHJKLMNOPQRSTUVWXYZABC-Two-way chain table 26 English letters of the application of arbitrary input an integer, can achieve the following functions: 3 such as input, The output is: DEFGHJKLMNOPQRS