Thread: Circular linked list

I think yes! Cur would be pointing to first. Then the next of the last (the first) will be pointing to next of the first, so, no one will be pointing to first. But usually the linked list is a pointer to the first element.

>I am trying to make sure I am understanding what I am reading.
The best way to check your understanding is to write a small program that tests your assumptions:

Code:

/* Ugly quick code */
#include <iostream>

using namespace std;

struct node {
  int   data;
  node *next;
  node(int init, node *link)
    : data(init)
    , next(link)
  {}
};

int
main()
{
  node *head, *tail;

  head = new node(0, 0);
  head->next = head;
  tail = head;
  for (int i = 1; i < 10; i++) {
    tail->next = new node(i, head);
    tail = tail->next;
  }
  for (tail = head; tail->next != head; tail = tail->next) {
    cout<< tail->data <<endl;
  }
  cout<< tail->data <<endl<<endl;
  node *cur = tail->next;
  tail->next = cur->next;
  for (tail = head; tail->next != head; tail = tail->next) {
    cout<< tail->data <<endl;
  }
  cout<< tail->data <<endl;
}

This clearly doesn't work when you run it. The problem is that tail->next will never point to head because head is the node that was removed from the list. You need to reseat head too:

Code:

node *cur = tail->next;
tail->next = cur->next;
head = tail->next;