/**
* Definition for singly-linked list.
* class ListNode {
* int val;
* ListNode next;
* ListNode(int x) {
* val = x;
* next = null;
* }
* }
*/
public class Solution {
public void reorderList(ListNode head) {
if (head == null || head.next == null) {
return;
}
nodeChange(head, head.next);
System.out.println(head);
}
private void nodeChange(ListNode pre, ListNode last) {
if (last == null || last.next == null) {
return;
}
ListNode temp = last;
while (temp.next.next != null) {
temp = temp.next;
}
pre.next = temp.next;
pre.next.next = last;
temp.next = null;
nodeChange(pre.next.next, last.next);
}
}
我的解法使用了递归变化,不知道是不是满足题目要求的使用原地算法