#include <iostream>
using namespace std;

int main()
{
	int num;
	int *ptr;

	num = 5;
	ptr = &num;	// ptr contains the address of num;

	cout << "the value of num is " << num << endl;
	cout << "the address of num in memory is " << ptr << endl;
	cout << *ptr << endl;   // displaying the value of memory location pointed by ptr. 
	                        // this value must be the same as the value num since 
                            // the same memory location is displayed

	cout << endl;
	int *p = new int;
	*p = 4.5;
	cout << p << endl;  // displaying a dynamically allocated memory address. It is quite 
                        // different than the address stored in ptr. The reason is that 
                        // variables are allocated from a different portion of memory

	return 0;
}