Linked List Components
<p>You are given the <code>head</code> of a linked list containing unique integer values and an integer array <code>nums</code> that is a subset of the linked list values.</p>

<p>Return <em>the number of connected components in </em><code>nums</code><em> where two values are connected if they appear <strong>consecutively</strong> in the linked list</em>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/0800-0899/0817.Linked%20List%20Components/images/lc-linkedlistcom1.jpg" style="width: 424px; height: 65px;" />
<pre>
<strong>Input:</strong> head = [0,1,2,3], nums = [0,1,3]
<strong>Output:</strong> 2
<strong>Explanation:</strong> 0 and 1 are connected, so [0, 1] and [3] are the two connected components.
</pre>

<p><strong class="example">Example 2:</strong></p>
<img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/0800-0899/0817.Linked%20List%20Components/images/lc-linkedlistcom2.jpg" style="width: 544px; height: 65px;" />
<pre>
<strong>Input:</strong> head = [0,1,2,3,4], nums = [0,3,1,4]
<strong>Output:</strong> 2
<strong>Explanation:</strong> 0 and 1 are connected, 3 and 4 are connected, so [0, 1] and [3, 4] are the two connected components.
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li>The number of nodes in the linked list is <code>n</code>.</li>
	<li><code>1 &lt;= n &lt;= 10<sup>4</sup></code></li>
	<li><code>0 &lt;= Node.val &lt; n</code></li>
	<li>All the values <code>Node.val</code> are <strong>unique</strong>.</li>
	<li><code>1 &lt;= nums.length &lt;= n</code></li>
	<li><code>0 &lt;= nums[i] &lt; n</code></li>
	<li>All the values of <code>nums</code> are <strong>unique</strong>.</li>
</ul>
Array; Hash Table; Linked List
/**
 * Definition for singly-linked list.
 * function ListNode(val, next) {
 *     this.val = (val===undefined ? 0 : val)
 *     this.next = (next===undefined ? null : next)
 * }
 */
/**
 * @param {ListNode} head
 * @param {number[]} nums
 * @return {number}
 */
var numComponents = function (head, nums) {
    const s = new Set(nums);
    let ans = 0;
    while (head) {
        while (head && !s.has(head.val)) {
            head = head.next;
        }
        ans += head != null;
        while (head && s.has(head.val)) {
            head = head.next;
        }
    }
    return ans;
};
