题目链接：https://www.51nod.com/onlineJudge/questionCode.html#!problemId=1639
#include <bits/stdc++.h>
using namespace std;
typedef long long LL;
];
int main()
{
ans[]=;
;i<=;i++)
ans[i]=ans[i-]**(i-)/(*i-);
int n;
while(cin>>n)
cout<<ans[n]<<endl;
}