assign the address of a public member of an object to a pointer and then access that member by using the pointer : object pointer « Pointer « C++ Tutorial

1. C++ Tutorial
2. Pointer
3. object pointer

#include <iostream>
using namespace std;
   
class cl {
public:
  int i;
  cl(int j) { i=j; }
};
   
int main()
{
  cl ob(1);
  int *p;
   
  p = &ob.i; // get address of ob.i
   
  cout << *p; // access ob.i via p
   
  return 0;
}