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-# Algorithms 2019-2020 Python LEETCODE
-
-Check branches for information.
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+# Binary tree
+
++ [Maximum Depth of Binary Tree](#maximum-depth-of-binary-tree)
+
+## Maximum Depth of Binary Tree
+
+https://leetcode.com/problems/maximum-depth-of-binary-tree/
+
+```python
+# Definition for a binary tree node.
+# class TreeNode(object):
+#     def __init__(self, val=0, left=None, right=None):
+#         self.val = val
+#         self.left = left
+#         self.right = right
+class Solution(object):
+    def maxDepth(self, root):
+        """
+        :type root: TreeNode
+        :rtype: int
+        """
+        if not root:
+            return 0
+        return max(self.maxDepth(root.left), self.maxDepth(root.right)) + 1
+
+```
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