LeetCode Remove Duplicates from Sorted List

nothing to it.

ListNode *deleteDuplicates(ListNode *head) {
	if(head==NULL||head->next==NULL)
		return head;
	ListNode *p=head,*s=NULL;
	ListNode *q=head->next;
	while(q!=NULL)
	{
		if (p->val!=q->val)
		{
			p = q;
			q = q->next;
		}
		else
		{
			s = q;
			q = q->next;
			p->next = s->next;
			delete s;
		}
	}
	return head;
}