diff --git a/notes/55.1 二叉树的深度.md b/notes/55.1 二叉树的深度.md
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@@ -6,7 +6,7 @@
从根结点到叶结点依次经过的结点（含根、叶结点）形成树的一条路径，最长路径的长度为树的深度。
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## 解题思路
diff --git a/notes/pics/offer-tree-depth.png b/notes/pics/offer-tree-depth.png
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