@[liumusi2022](/user/720390) x存的是前序遍历。
应将
```cpp
s = x.find(c)
```
改为
```cpp
s = y.find(c)
```
by zhizhi_c @ 2022-09-27 08:20:37
@[liumusi2022](/user/720390) 还有
```cpp
if(s + 1 <= len - 1)
{
dfs(x.substr(s + 1), y.substr(s + 1));
}
```
怎么是≤len-1呢，下标最大才是len-1
应改为
```cpp
if(s + 1 < len - 1)
{
dfs(x.substr(s + 1), y.substr(s + 1));
}
```
by zhizhi_c @ 2022-10-03 08:58:23
@[zhizhi_c](/user/768144) 好的，谢谢
by liumusi2022 @ 2022-10-06 14:59:33