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.Note:
If N is the length of the linked list given by head, 1 <= N <= 10000.
The value of each node in the linked list will be in the range [0, N - 1].
1 <= G.length <= 10000.
G is a subset of all values in the linked list.
/**
* 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) {
Set<Integer> Gset = new HashSet();
for (int x: G) Gset.add(x);
ListNode cur = head;
int ans = 0;
while (cur != null) {
if (Gset.contains(cur.val) &&
(cur.next == null || !Gset.contains(cur.next.val)))
ans++;
cur = cur.next;
}
return ans;
}
}