unsigned long long
by する @ 2022-04-09 09:46:48
@[asdfghjkl010218](/user/602256) [https://www.luogu.com.cn/record/64266200](https://www.luogu.com.cn/record/64266200)
by farmer_snack @ 2022-04-09 10:53:55
@[违规用户名SJ1DJMXN](/user/581445) 谢谢啦
by asdfghjkl010218 @ 2022-04-09 10:59:04
凹凸粉吗？（在洛谷聊这个是不是不太好）
by AIMEE11 @ 2022-07-18 19:18:48
```c
#include<iostream>
using namespace std;
int main(){
unsigned long long x;
cin>>x;
cout<<x*(x-1)/2*(x-2)/3*(x-3)/4<<endl;
return 0;
}
```
by nemo2010 @ 2022-07-21 18:49:20