Thu. Dec 12th, 2024

We are given head, the head node of a linked list containing unique integer values.

We are also given the list G, a subset of the values in the linked list.

Return the number of connected components in G, where two values are connected if they appear consecutively in the linked list.

Example 1:

Input: 
head: 0->1->2->3
G = [0, 1, 3]
Output: 2
Explanation: 
0 and 1 are connected, so [0, 1] and [3] are the two connected components.

Example 2:

Input: 
head: 0->1->2->3->4
G = [0, 3, 1, 4]
Output: 2
Explanation: 
0 and 1 are connected, 3 and 4 are connected, so [0, 1] and [3, 4] are the two connected components.
/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) { val = x; }
 * }
 */
class Solution {
    public int numComponents(ListNode head, int[] G) {
        List<Integer> gList = IntStream.of(G).boxed().collect(Collectors.toList());
        ListNode temp = head;
        List<Integer> componentList = new ArrayList<Integer>();
        int counter = 0;
        while(temp != null){
            if(gList.contains(temp.val)){
                componentList.add(temp.val);
            }else{
                //System.out.println(componentList);
                if(componentList.size() > 0)
                    counter++;
                componentList.clear();
            }
            temp = temp.next;
        }
        //System.out.println(componentList);
        if(componentList.size() > 0)
            counter++;
        componentList.clear();
        
        return counter;
    }
}