push_down 应该是 `(ta[k<<1]+=ta[k]*tm[k])%=mod;` 吧
by bloodstalk @ 2023-10-19 20:06:50
no?
by SFlyer @ 2023-10-19 21:27:47
哦，应该是
```cpp
ta[k<<1] = (ta[k] + ta[k<<1]*tm[k]) % mod;
ta[k<<1|1] = (ta[k] + ta[k<<1|1]*tm[k]) % mod;
```
这样就行了（
by bloodstalk @ 2023-10-19 22:47:30
@[bloodstalk](/user/231543) /bx
by SFlyer @ 2023-10-20 08:55:18