Construction of Circular linked list help;

[james16]

I am trying to construct a circular linked list of integers but I am not able to compile the program because of a segmentation fault in my constructor method.

  7 class princelist
  8 {
  9     private:
 10     struct ListNode
 11     {
 12         int item;
 13         ListNode *next;
 14     };
 15     ListNode *_head;
 16     int _size;
 25     public:
 26     princelist(int n)
 27     {
 28         _size = n;
 29         //head = NULL;
 30
 31         ListNode *newptr = _head;
 32
 33         for (int i = 1; i <= n; i++)
 34         {
 35             newptr = new ListNode;
 36             newptr->item = i;
 37             newptr = newptr->next;
 38            
 39             cout << "yes" << endl;
 40             cout << _head->item << endl;
 41         }
 42          cout << "out for loop" << endl;
 43          // newptr = _head (commented out because this statement gives me a compilation error also)
 43     }
 44     };
 46     int main(){
 47     princelist test(3);
 48     return 0;
 49     }

Ouput

yes
0
yes
0
yes
0
out of for loop
Aborted(core dumped)



Anyone have any idea why my head->item is 0 instead of the first value of i which is 1 and any idea why there is a aborted(core dumped) error?

[ne555]

ListNode *newptr = _head;

for (int i = 1; i <= n; i++)
{
	newptr = new ListNode;
	newptr->item = i;
	newptr = newptr->next;

	cout << "yes" << endl;
	cout << _head->item << endl;
}

You never modify `head'.


> I am not able to compile the program because of a segmentation fault
A segmentation fault is a runtime error, so your program did compile.

[james16]

lol hahaha i see the issue thanks alot man!