#include <stdio.h>
#include <stdlib.h>
 
struct node {
      int value;
      struct node * next;
  };
 
  struct node* function1(struct node *p) {
       p = p->next;
       return p;
   }
 
void function2(struct node **p) {
    (*p) = (*p)->next;
  }
 
int main(void) {
 
	struct node * p1 = (struct node*)calloc(1, sizeof(struct node));
	struct node * p2 = (struct node*)calloc(1, sizeof(struct node));
	p1->next = NULL;
	p2->next = NULL;
	printf("p1 = %p; and p2 = %p\n", p1, p2);
	function1(p1);
	function2(&p2);
	printf("p1 = %p; and p2 = %p", p1, p2);
	//head = funcion1(head);
	//function2(&head);
	return 0;
}
 

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