@[李嘉昇](/user/357378) 您被卡精度了，需要每次加的时候乘上 $10^6$，最后再除掉：
```cpp
#include<stdio.h>
long double s,x;
int main()
{
while(scanf("%Lf",&x)!=EOF)s+=x*1e6;
printf("%.5Lf",s/1e6);
return 0;
}
```
by hensier @ 2020-10-03 15:25:02
用double而不是float，不然精度会炸
by 血色黄昏 @ 2020-10-03 15:25:28
写了
by ajahjahah @ 2020-10-03 15:30:40
@[李嘉昇](/user/357378) 用double
by Smile_Cindy @ 2020-10-03 15:46:12