题目:

剑指 Offer 06. 从尾到头打印链表
输入一个链表的头节点,从尾到头反过来返回每个节点的值(用数组返回)。

示例 1
输入:head = [1,3,2]
输出:[2,3,1]

代码:

class Solution {
public int[] reversePrint(ListNode head) {
ListNode temp = head;
int len = 0;
while(temp != null){
len++;
temp = temp.next;
}
int[] arr = new int[len];
int index = len-1;
temp = head;
while(temp != null){
arr[index--] = temp.val;
temp = temp.next;
}
return arr;
}
}

时间复杂度:O(n)
空间复杂度:O(n)