Untitled

#include <iostream>
using namespace std;

long long factorial(int a) {
	long long fr = 1;
	for (int i = 1; i <= a; i++) {
		fr *= i;
	}
	return fr;
	
}
int main() {
	setlocale(LC_ALL, "Russian");
	int a;
	cin >> a;
	factorial(a);
}