- duanjiajun's blog
求阶乘
- 2023-9-10 20:26:12 @
#include <bits/stdc++.h>
using namespace std;
int main() {
int n;
double e = 1, ic = 1;
cin >> n;
for (int i = 1; i <= n; i++) {
ic *= i; // ic为因数吧应该···
e = e + 1.0 / ic;//是甚么意思呢布吉岛
}
cout << fixed << setprecision(10) << e << endl;
return 0;
}