1. ArrayList 和 LinkedList 的区别
http://pengcqu.iteye.com/blog/502676
2. How to reverse LinkedList
http://www.java2blog.com/2014/07/how-to-reverse-linked-list-in-java.html
/** * Definition for ListNode. * public class ListNode { * int val; * ListNode next; * * ListNode(int val) { * this.val = val; * this.next = null; * } * } */ public class Solution { /** * @param head: The head of linked list. * @return: The new head of reversed linked list. */ public ListNode reverse(ListNode head) { ListNode preNode = null; ListNode nextNode; ListNode curNode = head; while(curNode != null){ nextNode = curNode.next; curNode.next = preNode; preNode = curNode; curNode = nextNode; } return preNode;// write your code here } }