Java [Leetcode 203]Remove Linked List Elements

题目描述:

Remove all elements from a linked list of integers that have value val.

Example
Given: 1 --> 2 --> 6 --> 3 --> 4 --> 5 --> 6, val = 6
Return: 1 --> 2 --> 3 --> 4 --> 5

解题思路：

链表操作。

代码如下：

/**
* Definition for singly-linked list.
* public class ListNode {
*     int val;
*     ListNode next;
*     ListNode(int x) { val = x; }
* }
*/
public class Solution {
public ListNode removeElements(ListNode head, int val) {
ListNode res = new ListNode(0);
res.next = head;
ListNode point = head, pre = res;

while(point != null) {
if(point.val == val) {
if(point.next != null) {
point.val = point.next.val;
point.next = point.next.next;
} else {
point = null;
pre.next = null;
}
} else {
point = point.next;
pre = pre.next;
}
}
return res.next;
}
}