Function factorial

Codeforces_problems/Dreamoon and WIFI/solution.cpp:23–30

#include <iomanip>
using namespace std;
long long int factorial(int n) {
	long long int result = 1;
	while (n != 0) {
		result *= n;
		n--;
	}
	return result;
}
int main() {
	string str1, str2;
	cin >> str1 >> str2;