//reference and pointers

#include <iostream>
#include <string>

using namespace std; 

int main()
{
    int y, z;
    int* x, p; //pointer to integer

    //I set y
    y = 1;
    x = &y;  //x contains the address of y (& = reference operator)
    //p = x; //it raises an error!
    z = *x;  //z contains the value pointed (referenced) by x, which is equal to y

    cout << "y: " << y << endl;
    cout << "z (equal to y): " << z << endl; 
    cout << "x (address of y): " << x << endl; //hexadecimal memory address

    //now, I change y
    y = 2;
    cout << "now y is: " << *x << endl; //*x contains the updated value of y
    cout << "z: " << z << " (y not updated!)" << endl; //z contains the old value of y
    cout << "now x is: "<< x << " (the address of y does not change!)" << endl;

    return 0;     
}