Sum of array digits C++

/*
    <3
*/

#include <iostream>

using namespace std;

int main() {
    int size;
    cout << "Enter array size: ";
    cin >> size;
    int *arr = new int[size];
    cout << "Enter " << size << " elements with a space: ";
    for (int i = 0; i < size; i++)
        cin >> arr[i];

    cout << "Old array: ";
    for (int i = 0; i < size; i++)
        cout << arr[i] << " ";

    for (int i = 0; i < size; i++) {
        int sum = 0;
        while (arr[i] != 0) {
            sum += arr[i] % 10;
            arr[i] = arr[i] / 10;
        }
        arr[i] = sum;
    }

    cout << endl << "New array: ";
    for (int i = 0; i < size; i++)
        cout << arr[i] << " ";

    delete[] arr;
    return 0;
}