maximum depth of binary tree solution

Author: parkhojeong

maximum-depth-of-binary-tree/parkhojeong.py

@@ -0,0 +1,15 @@
+# Definition for a binary tree node.
+# class TreeNode:
+#     def __init__(self, val=0, left=None, right=None):
+#         self.val = val
+#         self.left = left
+#         self.right = right
+class Solution:
+    def maxDepth(self, root: Optional[TreeNode]) -> int:
+        return self.dfs(root, 0)
+
+    def dfs(self, root, depth) -> int:
+        if not root:
+            return depth
+
+        return max(self.dfs(root.left, depth + 1), self.dfs(root.right, depth + 1))