Sum of Digits using Recursion in C++

#include <bits/stdc++.h>

using namespace std;

int Sum(int n) {
    return (n % 10 + (n >= 10 ? Sum(n / 10) : 0));
}

int main() {
    int n;
    cin >> n;
    cout << Sum(n) << '\n';
    return 0;
}