鏈表的翻轉

public ListNode reverseListNode(ListNode node){
?? ??? ?ListNode pre = null;
?? ??? ?ListNode now = node;//當前節點
?? ??? ?while (now !=null){
?? ??? ??? ?ListNode after = now.next;
?? ??? ??? ?now.next = pre;
?? ??? ??? ?pre = now;
?? ??? ??? ?now = after;
?? ??? ?}
?? ??? ?return node;
?? ?}