#include<cstdio>
#include<iomanip>
#include<iostream>
#include<cstring>
#include<algorithm>
#include<math.h>
#include <string>
#include<cmath>
using namespace std;
int n,a[1000],b[1000],up,tmp,x,kaishi,kaishi2,changdu,up2,tmp2;
int main()
{
    cin>>n;
    a[0]=1;
    for(int i=1; i<=n; i++)
    {
        for(int k=1; k<=i; k++)
        {
            up=0;
            for(int j=0; j<=1000; j++)
            {
                tmp=a[j]*k+up;
                a[j]=tmp%10;
                up=tmp/10;
            }
        }
        for(int i2=0; i2<=1000; i2++)
        {
            tmp2=a[i2]+b[i2]+up2;
            b[i2]=tmp2%10;
            up2=tmp2/10;

        }

        for(int j2=0; j2<=1000; j2++)
        {
            a[j2]=0;
        }
    }
    for(int i=1000; i>=0; i--)
    {   cout<<b[i];
        kaishi2=i;
        if(b[i]!=0)break;
    }
    for(int j=kaishi2; j>=0; j--)
    {
        cout<<b[j];
    }

}