题解 | #删除有序链表中重复的元素-I#
删除有序链表中重复的元素-I
http://www.nowcoder.com/practice/c087914fae584da886a0091e877f2c79
双指针:空间复杂度O(1),时间复杂度O(n)
public ListNode deleteDuplicates (ListNode head) { if(head==null){ return null; } // write code here ListNode pre = head; ListNode preNext = head.next; while(preNext!=null){ if(pre.val!=preNext.val){ pre.next=preNext; pre = preNext; } preNext=preNext.next; } pre.next=preNext; return head; }