多取几次余看看
by Keep_RAD @ 2021-08-07 12:57:29
在sum函数里
by Keep_RAD @ 2021-08-07 13:03:15
@[run_after_dream](/user/363069) 谢谢，我试试
by Heart_Of_Iron_4 @ 2021-08-07 19:40:09
@[run_after_dream](/user/363069) 试了一下，不行啊，还是10分
<https://www.luogu.com.cn/record/55235040>
by Heart_Of_Iron_4 @ 2021-08-07 19:43:34
再加mod?
防止减法为负
by Keep_RAD @ 2021-08-07 19:44:10
我把sum改成了
```cpp
inline long long sum(register int k)
{
register long long sm=0;
while(k>0)
{
sm=(sm+a[k])%mod;
k-=lowbit(k);
}
return sm;
}
```
by Heart_Of_Iron_4 @ 2021-08-07 19:46:32
sm+=mod 写一下
by Keep_RAD @ 2021-08-07 19:49:12
写了，还是10分<https://www.luogu.com.cn/record/55236109>
```cpp
inline long long sum(register int k)
{
register long long sm=0;
while(k>0)
{
sm+=mod;
sm=(sm+a[k])%mod;
k-=lowbit(k);
}
return sm;
}
```
by Heart_Of_Iron_4 @ 2021-08-07 19:52:41
```
#define int long long
signed main
```
by Hywel @ 2021-10-12 08:50:28
@[Hywel](/user/90510) 已AC，谢谢！
by Heart_Of_Iron_4 @ 2021-10-21 17:48:03