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diff --git a/docs/notes/剑指 offer 题解.md b/docs/notes/剑指 offer 题解.md
index 6c61ccec..1184cb0e 100644
--- a/docs/notes/剑指 offer 题解.md
+++ b/docs/notes/剑指 offer 题解.md
@@ -246,12 +246,14 @@ public String replaceSpace(StringBuffer str) {
从尾到头反过来打印出每个结点的值。
- 
+ 
## 解题思路
### 使用栈
+ 
+
```java
public ArrayList printListFromTailToHead(ListNode listNode) {
Stack stack = new Stack<>();
@@ -268,6 +270,8 @@ public ArrayList printListFromTailToHead(ListNode listNode) {
### 使用递归
+ 
+
```java
public ArrayList printListFromTailToHead(ListNode listNode) {
ArrayList ret = new ArrayList<>();
@@ -288,6 +292,8 @@ public ArrayList printListFromTailToHead(ListNode listNode) {
- 头结点是在头插法中使用的一个额外节点，这个节点不存储值；
- 第一个节点就是链表的第一个真正存储值的节点。
+ 
+
```java
public ArrayList printListFromTailToHead(ListNode listNode) {
// 头插法构建逆序链表
@@ -309,20 +315,6 @@ public ArrayList printListFromTailToHead(ListNode listNode) {
}
```
-### 使用 Collections.reverse()
-
-```java
-public ArrayList printListFromTailToHead(ListNode listNode) {
- ArrayList ret = new ArrayList<>();
- while (listNode != null) {
- ret.add(listNode.val);
- listNode = listNode.next;
- }
- Collections.reverse(ret);
- return ret;
-}
-```
-
# 7. 重建二叉树
[NowCoder](https://www.nowcoder.com/practice/8a19cbe657394eeaac2f6ea9b0f6fcf6?tpId=13&tqId=11157&tPage=1&rp=1&ru=/ta/coding-interviews&qru=/ta/coding-interviews/question-ranking)
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