LeetCode 206.チェーンテーブルjavaを反転

  : 1->2->3->4->5->NULL
  : 5->4->3->2->1->NULL

class Solution {
    public ListNode reverseList(ListNode head) {
        if (head == null || head.next == null) {
			return head;
		}
		ListNode headNode = reverseList(head.next);
		head.next.next = head;
		head.next = null;
		return headNode;
    }
}