/* Reference */
#include <stdio.h>
 
int main()
{
  int a = 5;
 
  printf("The value of a is: %d\n", a);
  printf("The address of a is: %p\n", &a);
 
  return 0;
}

/* Pointer */
#include <stdio.h>
 
int main()
{
  int a;
  int *p;
 
  a = 5;
  p = &a;
 
  printf("The value of a is: %d\n", a);
  printf("The address of a is: %p\n", &a);
  printf("The address of a is: %p\n", p);
 
  return 0;
}

/* Dereference */
#include <stdio.h>
 
int main()
{
  int a;
  int *p;
 
  a = 5;
  p = &a;
 
  printf("The value of a is: %d\n", a);
  printf("The value of a is: %d\n", *p);
  printf("The address of a is: %p\n", &a);
  printf("The address of a is: %p\n", p);
 
  *p = 10;
 
  printf("New value of a is: %d\n", a);
  printf("New value of a is: %d\n", *p);
  printf("The address of a is: %p\n", &a);
  printf("The address of a is: %p\n", p);
 
 
  return 0;
}

/* Uninitialize */
#include <stdio.h>
 
int main()
{
  int *p;
  int n = *p;
 
  printf("Uninitialized value of n is: %d\n", n);
  printf("Uninitialized value of p is: %p\n", p);
 
  return 0;
}