Check Strong Number in C++

1#include <iostream>
2using namespace std;
3
4int factorial(int n) {
5    if (n == 0 || n == 1) return 1;
6    return n * factorial(n - 1);
7}
8
9bool isStrong(int num) {
10    int original = num;
11    int sum = 0;
12    
13    while (num > 0) {
14        int digit = num % 10;
15        sum += factorial(digit);
16        num /= 10;
17    }
18    
19    return sum == original;
20}
21
22int main() {
23    int num;
24    cout << "Enter a number: ";
25    cin >> num;
26    
27    if (isStrong(num)) {
28        cout << num << " is a Strong number" << endl;
29    } else {
30        cout << num << " is not a Strong number" << endl;
31    }
32    
33    return 0;
34}