Simple recursive code for factorial solution

factorial.cpp

#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;

int factorial(int n){
    if(n == 0){
        return 1;
    }
    else{
        return n * factorial(n-1);
    }
}


int main(){
    
    int n;
    cout << "Enter number: ";
    cin >> n;
    cout << "The answer is: " << factorial(n) << endl;
    return 0;
}