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
本题比较简单，构造一个dummy头即可。
移位删除时，存在与不存在的删除办法不同
/**
* 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) {
if (head == null) return head;
ListNode dummy = new ListNode(0);
dummy.next = head;
ListNode prev = dummy;
ListNode curr = dummy.next;
while(curr.next != null) {
if(curr.val == val) {
prev.next = curr.next;
curr = curr.next;
}
else {
prev = prev.next;
curr = curr.next;
}
}
if(curr.next == null) {
if(curr.val == val) prev.next = null;
}
return dummy.next;
}
}
203. Remove Linked List Elements
原文：http://www.cnblogs.com/Raymond-Yang/p/5216296.html