@[wyf_sinon](/user/540177)
```cpp
f1[i+n][i]=0;f2[i+n][i]=0;
```
改为
```cpp
f1[i+n][i+n]=0;f2[i+n][i+n]=0;
```
by xuhaotian @ 2023-10-13 18:36:22
[亲测有效](https://www.luogu.com.cn/record/129124236)
by xuhaotian @ 2023-10-13 18:36:51
@[xuhaotian](/user/576448) oh 我忘记这里区间也变了awa 拜谢
by wyf_sinon @ 2023-10-13 21:36:42