#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define MAXN 3000
int f[MAXN];
int main()
{
int n,i,j;
memset(f,0,sizeof(f));
f[0]=1;
while(scanf("%d",&n) != EOF ){
for(i=2;i<=n;i++){
int c=0;
for(j=0;j<MAXN;j++){
int s=f[j]*i+c;
f[j]=s%10;
c=s/10;
}
}
for(j=MAXN-1;j>=0;j--)if(f[j]) break;
for(i=j;i>=0;i--)
printf("%d",f[i]);
printf("\n");
memset(f,0,sizeof(f));
f[0]=1;
}
return 0;
}