#include <stdio.h>

int main(int argc, char* argv[]) {

  int i = 7;        // variable i has a higher address than that of j,
  int j = -1;       // for example, &i == 0x7ffffce2d96c
                    // &j == 0x7ffffce2d968
  int *pi = &i;
  int *pj = &j;

  printf(" i = %d\n", i);
  printf(" j = %d\n", j);
  printf(" pi= %p\n", pi);
  printf(" pj= %p\n", pj);
  printf(" data pointed to by pi= %d\n", *pi);
  printf(" data pointed to by pj= %d\n\n", *pj);

  *pi = 6;
  pi = pi - 1;   // pi - 1 makes pi point to the address of pj
                 // now the address pi and pj are the same,
                 // so are the contents
  printf(" i = %d\n", i);
  printf(" j = %d\n", j);
  printf(" pi= %p\n", pi);
  printf(" pj= %p\n", pj);
  printf(" data pointed to by pi= %d\n", *pi);
  printf(" data pointed to by pj= %d\n\n", *pj);

  return 0;
}