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：
JAVA实现如下：
public ListNode removeElements(ListNode head, int val) {
ListNode root=new ListNode(val+1),temp=root;
root.next=head;
while(temp.next!=null){
if(temp.next.val==val)
temp.next=temp.next.next;
else temp=temp.next;
}
return root.next;
}
