#include<bits/stdc++.h>
using namespace std;

int a[120],b[120],n;
void add(int *a , int *b){
	for(int i = 1;i <= 120;i++){
		int c;
		b[i] += a[i] + c;
		c = b[i] / 10;
		b[i] %= 10;
	}
}
void cheng(int *a , int c){
	for(int i = 1;i <= 120;i++){
		int b;
		a[i] *= c + b;
		c = a[i] / 10;
		a[i] %= 10;
	}
}

int main(){
	scanf("%d",&n);
	a[1] = 1;
	for(int i = 1;i <= n;i++){
		cheng(a , i);
		add(a , b);
	}
	bool flag = 0;
	for(int  i = 120;i >= 1;i--){
		if(b[i] != 0){
			flag = 1;
		}
		if(flag){
			printf("%d",b[i]);
		}
	}
	return 0;
}