题:https://leetcode.com/problems/remove-duplicates-from-sorted-list/description/
题目
Given a sorted linked list, delete all duplicates such that each element appear only once.
Example 1:
Input: 1->1->2
Output: 1->2
Example 2:
Input: 1->1->2->3->3
Output: 1->2->3
题目大意
去除 有序链表 中的重复值
思路
方法一
对与当前 node,找下个 与node 不用的结点,将当前node指向下个 node。
/**
* Definition for singly-linked list.
* public class ListNode {
* int val;
* ListNode next;
* ListNode(int x) { val = x; }
* }
*/
class Solution {
public ListNode deleteDuplicates(ListNode head) {
ListNode lp = head;
while(lp!=null){
ListNode p = lp.next;
while(p!=null && lp.val == p.val)
p = p.next;
lp.next = p;
lp = lp.next;
}
return head;
}
}
方法二
若下个node 与当前node不同,向下遍历;否则 提出下个node。
/**
* Definition for singly-linked list.
* public class ListNode {
* int val;
* ListNode next;
* ListNode(int x) { val = x; }
* }
*/
class Solution {
public ListNode deleteDuplicates(ListNode head) {
if(head == null)
return head;
ListNode p = head;
while(p.next!=null){
if(p.next.val == p.val){
p.next = p.next.next;
}
else{
p = p.next;
}
}
return head;
}
}