#include <iostream>

using namespace std;

int main()
{
    //we use pointers to save memory.

    int x = 25; //base integer
    int *p = x;
    cout << p << endl;
    //this will output the memory address of p. it's an unnamed memory location



    int y = 25; //base integer
    int *q = &y;  //using the address of operator
    cout << q << endl;
    //this will output the memory address of y

    //cout << *p << endl; //this won't work. it will crash
    cout << *q << endl;   //dereferencing q. This will print the value stored at the memory location q is pointing to

    x = x + 5;
    cout << x << endl;
    //x = *p + 5;
    //cout << x << endl;  //crashes.


    y = *q + 5; //25 + 5
    cout << y <<endl;

    *q = *q + 5;  //30 + 5
    cout << *q << endl;
    cout << y <<endl;  //both will display 35. We used the pointer to change the value at the memory location (y)

    cout << &*q << endl;  //& and * cancel out each other. same as writing q.

}