#include <iostream>
#include <string.h>
using namespace std;
const int MAXN = 100000;
const int N = 8000;
struct bign {
int len;
int s[N];
bign() {
this -> len = 1;
memset(s, 0, sizeof(s));
}
bign (int number) {*this = number;}
bign (const char* number) {*this = number;}
bign change(bign cur) {
bign now;
now = cur;
for (int i = 0; i < cur.len; i++)
now.s[i] = cur.s[cur.len - i - 1];
return now;
}
void delZore() {
bign now = change(*this);
while (now.s[now.len - 1] == 0 && now.len > 1) {
now.len--;
}
*this = change(now);
}
void put() {
delZore();
printf("%d", s[0]);
for (int i = 1; i < len; i++)
printf("%05d", s[i]);
}
bign operator = (const char *number) {
memset(s, 0, sizeof(s));
int dist = strlen(number);
int k = dist % 8;
for (int i = 0; i < k; i++)
s[0] = s[0] * 10 + number[i] - '0';
int cnt = 0;
for (int i = k; i < dist; i++, cnt++)
s[cnt / 8 + 1] = s[cnt / 8 + 1] * 10 + number[i] - '0';
len = cnt / 8 + 1;
return *this;
}
bign operator = (int number) {
char string[N];
sprintf(string, "%d", number);
*this = string;
return *this;
}
bign operator * (const bign &cur){
bign sum, a, b;
sum.len = 0;
a = a.change(*this);
b = b.change(cur);
for (int i = 0; i < a.len; i++){
int g = 0;
for (int j = 0; j < b.len; j++){
int x = a.s[i] * b.s[j] + g + sum.s[i + j];
sum.s[i + j] = x % MAXN;
g = x / MAXN;
}
sum.len = i + b.len;
while (g){
sum.s[sum.len++] = g % MAXN;
g = g / MAXN;
}
}
return sum.change(sum);
}
};
int main() {
int n;
while (scanf("%d", &n) == 1) {
bign sum = 1;
for (int i = 2; i <= n; i++) {
bign now = i;
sum = sum * now;
}
sum.put();
printf("\n");
}
return 0;
}
