/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode() {}
 *     ListNode(int val) { this.val = val; }
 *     ListNode(int val, ListNode next) { this.val = val; this.next = next; }
 * }
 */
class Solution {
    public int numComponents(ListNode head, int[] nums) {
        Set<Integer> numsSet = new HashSet<Integer>();
        for(int num: nums) numsSet.add(num);
        boolean inSet = false;
        int res = 0;
        while(head != null){
            if(numsSet.contains(head.val)){
                if(!inSet)
                {
                    inSet = true;
                    res ++ ;
                }
            }
            else{
                inSet = false;
            }
            head = head.next;
        }

        return res;
    }
}