#include 
        
          struct node {
      int val;     node* next; }; typedef node* list_node; list_node create(int n ) {
          list_node head , temp ,pre;     head = new node;     pre = head; while ( n -- )     {
              temp = new node;         scanf("%d" , &temp->val);         pre->next = temp;         pre = temp;     }     pre->next = NULL; return head; } int add(list_node &head,int pos,int value) {
          list_node temp = head; int count = 0 ; while ( temp->next != NULL)     {
              temp =temp->next;         count ++; if (count == pos ) break;     } if (temp->next == NULL) return -1; else     {
              list_node n = new node;         n->val = value;         n->next = temp->next ;         temp->next = n ; return 1;     } } int cont(const list_node head) {
          list_node temp = head; int count = 0 ; while ( temp ->next != NULL)     {
              temp = temp->next;         count ++;     } return count; } node* reverse( list_node temp , list_node &head ) {
      if ( temp == NULL || temp->next == NULL)     {
              head->next = NULL;         head = temp; return head;     }     list_node tmp = reverse( temp->next , head);     tmp->next = temp; return temp; } int del(list_node &head , int pos) {
      int count = 0 ;     list_node temp = head; while ( temp->next != NULL)     {
              temp = temp->next ;         count ++; if ( count == pos - 1 ) break;     } if ( temp->next == NULL )     {
      return -1;     } else     {
      if ( temp->next->next == NULL)             temp->next = NULL; else             temp->next = temp->next->next; return 1;     } } int main() {
          list_node head = create(5);     del(head,3);     reverse(head,head); return 0 ; }