Listing 1

#include <stdio.h>

class X
   {
public:
   int i;
   int &ri;
   X(int *p) : i(*p), ri(*p) { }
   };

int main()
   {
   int n = 3;
   X x1(&n};         // x1.r refers to n
   ++x1.ri;         // increment n
   printf ("%d\n", n);
   return 0;
   }
// End of File