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;}