题解 | #n的阶乘#

#include <iostream>
using namespace std;

long long Factorial(long long n){
    if(n >= 1)
        return n * Factorial(n - 1);
    else
        return 1;
}

int main() {

    long long n;
    cin >> n;
    cout << Factorial(n);
    return 0;
}