Bypassing encapsulation with typecast to struct

cpp_break_struct.cpp

#include <iostream>
using namespace std;

class Contact
{
    private:
        int mobile_number;           // private variable
        int home_number;             // private variable
    public:
        Contact()                    // constructor
        {
            mobile_number = 12345678;
            home_number = 87654321;
        }
        void print_numbers()
        {
            cout << "Mobile number: " << mobile_number;
            cout << ", home number: " << home_number << endl;
        }
};

struct Contact_struct
{
    int mobile_number;
    int home_number;
};

int main()
{
    Contact Tony;
    Contact_struct * structured_Tony;

    Tony.print_numbers();

    structured_Tony = (Contact_struct *) & Tony;

    structured_Tony->mobile_number = 20;
    structured_Tony->home_number = 30;
    Tony.print_numbers();

    return 0;
}