203. 移除链表元素

示例:

输入: 1->2->6->3->4->5->6, val = 6
输出: 1->2->3->4->5

// 只有下个节点不是要删除的节点才更新current
if (!next || next.val !== val) {
    current =  next;
}

/*
 * @lc app=leetcode id=203 lang=javascript
 *
 * [203] Remove Linked List Elements
 *
 * https://leetcode.com/problems/remove-linked-list-elements/description/
 *
 * algorithms
 * Easy (35.32%)
 * Total Accepted:    211.9K
 * Total Submissions: 598.6K
 * Testcase Example:  '[1,2,6,3,4,5,6]\n6'
 *
 * Remove all elements from a linked list of integers that have value val.
 *
 * Example:
 *
 *
 * Input:  1->2->6->3->4->5->6, val = 6
 * Output: 1->2->3->4->5
 *
 *
 */
/**
 * Definition for singly-linked list.
 * function ListNode(val) {
 *     this.val = val;
 *     this.next = null;
 * }
 */
/**
 * @param {ListNode} head
 * @param {number} val
 * @return {ListNode}
 */
var removeElements = function(head, val) {
    const dummy = {
        next: head
    }
    let current = dummy;

    while(current && current.next) {
        let next = current.next;
        if (next.val === val) {
            current.next = next.next;
            next = next.next;
        }

        if (!next || next.val !== val) {
            current =  next;
        }
    }

    return dummy.next;
};