仔细审题哦，n可以等于0的，你缺一个特判
by JamesZhan @ 2023-06-26 15:15:39
@[xuanbrother](/user/823847)
@[JamesZhan](/user/866321)
这道题似乎直接用公式也能AC，代码如下:
```
#include <bits/stdc++.h>
using namespace std;
int main() {
double n, sum;
cin >> n;
sum = pow (((1 + sqrt(5)) / 2), n) - pow (((1 - sqrt(5)) / 2), n);
sum /= sqrt(5);
printf("%.2lf", sum);
return 0;
}
```
by midsummer_zyl @ 2023-06-29 11:36:48
@[JamesZhan](/user/866321) @[midsummer_zyl](/user/1025321) 明白了，感谢！
by xuanbrother @ 2023-07-01 12:40:02