@[BenSolo](/user/995791)
对于
100
100%的数据，
n<=1e7
开数组需要开很大，并且可能会编译错误
建议代码如下：
```cpp
#include <bits/stdc++.h>
using namespace std;
int main() {
int n, a, b ,c;
double sum1 = 0, sum2 = 0;
cin >> n;
for (int i = 1; i <= n; i++) {
cin >> a;
sum1 += a;
}
for (int i = 1; i <= n; i++) {
cin >> b;
sum2 += b;
}
printf("%.6lf", (sum1 * 3 - sum2 * 2) / (sum1 - sum2));
return 0;
}
```
by midsummer_zyl @ 2023-07-05 18:42:17