diff --git a/problems/0102.二叉树的层序遍历.md b/problems/0102.二叉树的层序遍历.md
index 220232a2..21f5147d 100644
--- a/problems/0102.二叉树的层序遍历.md
+++ b/problems/0102.二叉树的层序遍历.md
@@ -562,6 +562,45 @@ public class N0107 {
 }
 ```
 
+```java
+/**
+ * 思路和模板相同, 对收集答案的方式做了优化, 最后不需要反转
+ */
+class Solution {
+    public List<List<Integer>> levelOrderBottom(TreeNode root) {
+        // 利用链表可以进行 O(1) 头部插入, 这样最后答案不需要再反转
+        LinkedList<List<Integer>> ans = new LinkedList<>();
+        
+        Queue<TreeNode> q = new LinkedList<>();
+
+        if (root != null) q.offer(root);
+
+        while (!q.isEmpty()) {
+            int size = q.size();
+
+            List<Integer> temp = new ArrayList<>();
+
+            for (int i = 0; i < size; i ++) {
+                TreeNode node = q.poll();
+                
+                temp.add(node.val);
+                
+                if (node.left != null) q.offer(node.left);
+
+                if (node.right != null) q.offer(node.right);
+            }
+
+            // 新遍历到的层插到头部, 这样就满足按照层次反序的要求
+            ans.addFirst(temp);
+        }
+
+        return ans;
+    }
+}
+```
+
+
+
 go:
 
 ```GO
@@ -3013,4 +3052,3 @@ impl Solution {
 <a href="https://programmercarl.com/other/kstar.html" target="_blank">
   <img src="../pics/网站星球宣传海报.jpg" width="1000"/>
 </a>
-