使用递归实现N重循环，这里的N是不确定的。此代码实现的功能描述如下：

1. 有一个字符串的矩阵，用vector< vector< CStirng > > 表示

2. 行与行之间进行排列组合

3. 输出所有组合的字符串-Recursive use of re-implementation cycle of N, where N is uncertain. This code describes the implementation of the function as follows: 1. There is a string matrix, with vector < vector < CStirng> >　express 2. Line and line 3 between the permutation and combination. Output for all combinations of string