题目

给定一个已排序的链表的头 head ， 删除所有重复的元素，使每个元素只出现一次 。返回 已排序的链表 。
示例 1：
输入：head = [1,1,2]
输出：[1,2]
示例 2：
输入：head = [1,1,2,3,3]
输出：[1,2,3]

分析

用一个指针从头结点开始遍历，如果当前元素和下个元素一致则更新当前指针的next结点为下个结点的下个结点，反之指针后移

public class LinkNode {int val;LinkNode next;public LinkNode(int data) {this.val = data;this.next = null;}
}
public class LinkList {LinkNode head;public LinkList() {this.head = null;}public LinkNode getHead() {return this.head;}//添加元素public void addNode(int data) {LinkNode node = new LinkNode(data);if (this.head == null) {this.head = node;} else {LinkNode cur = this.head;while(cur.next != null) {cur = cur.next;}cur.next = node;}}//正序打印public void print(LinkNode node) {while(node != null) {System.out.print(node.val);System.out.print(" ");node = node.next;}System.out.println();}public void deleteRepeate() {LinkNode pNode = this.head;while(pNode != null && pNode.next != null) {if(pNode.val == pNode.next.val) {pNode.next = pNode.next.next;} else {pNode = pNode.next;}}print(this.head);}}
public class removeDuplicatesfromSortedList {public static void main(String[] args) {LinkList list = new LinkList();list.addNode(1);list.addNode(1);list.addNode(2);list.addNode(3);list.addNode(3);list.deleteRepeate();}
}