diff --git a/notes/面试总结.md b/notes/面试总结.md
index a03e93d3..b3e18aff 100644
--- a/notes/面试总结.md
+++ b/notes/面试总结.md
@@ -538,23 +538,23 @@ public TreeLinkNode GetNext(TreeLinkNode pNode) {
 
 ```python
 def GetNext(self, pNode):
-        # write code here
-        # pNode is None
-        if not pNode:
-            return pNode
-        if pNode.right:
-            node = pNode.right
-            while node.left:
-                node = node.left
-            return node
-        else:
-            while pNode.next:
-                parent = pNode.next
-                if parent.left == pNode:
-                    return parent
-                pNode = pNode.next
-        # pNode not have the next node
-        return None
+    # write code here
+    # pNode is None
+    if not pNode:
+        return pNode
+    if pNode.right:
+        node = pNode.right
+        while node.left:
+            node = node.left
+        return node
+    else:
+        while pNode.next:
+            parent = pNode.next
+            if parent.left == pNode:
+                return parent
+            pNode = pNode.next
+    # pNode not have the next node
+    return None
 ```
 # 9. 用两个栈实现队列