bilangan faktorial c++

#include <stdio.h>
long int faktorial (unsigned int n){
if (n == 0 || n == 1)
    return 1;
else
    return n * faktorial(n-1);
}
int main(){
    int n;
    long int hasil;
    printf("n = ");
    scanf("%d", &n);
    hasil = faktorial(n);
    printf("%d! = %ld", n, hasil);
    return 0;
}