A company is planning to provide an extra discount to it's customers. Every order has an order ID associated with it which is a sequence of digits. The discount is calculated as the count of unique repeating digits in the order ID. Write a code to find the discount percentile given to the customers.

#include <iostream>
using namespace std;


int discount(int id) {
    int digits[10] = {0};

    while (id > 0) {
        int d = id % 10;
        digits[d]++;
        id /= 10;
    }

    int res = 0;
    for (int i=0; i<10; i++) {
        if (digits[i] > 1) {
            res++;
        }
    }
    return res;
}


int main() {
    int id;

    cout << "Enter the customer ID: ";
    cin >> id;
    int disc = discount(id);
    cout << "The discount is " << disc << "%";

    return 0;
}