Leetcode203-removeLinkedListElements

Description

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

Example

1 2	Input: 1->2->6->3->4->5->6, val = 6 Output: 1->2->3->4->5

Solution

/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) { val = x; }
 * }
 */
class Solution {
    public ListNode removeElements(ListNode head, int val) {
        if (head == null) return head;
        ListNode dummy = new ListNode(0);
        dummy.next = head;
        ListNode cur = head;
        ListNode pre = dummy;
        while(cur != null){
            if (cur.val == val)
                pre.next = cur.next;
            else pre = cur;
            cur = cur.next;
        }
        return dummy.next;
    }
}