摘要：
```C++ void swap(char& a, char& b){ char temp = a; a = b; b = temp; } void pai(string& str, int start, int end, vector& res){ if(start == end){ string st = str; res.e... 阅读全文
摘要：
```C++ void swap(char& a, char& b){ char temp = a; a = b; b = temp; } void perm(vector& vec, int start, int end, vector>& res){ if(start == end){ vector re(end, 0); fo... 阅读全文