[변지협] Day18

leetcode3/변지협/v3/226. Invert Binary Tree.py

@@ -0,0 +1,27 @@
+# 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 invertTree(self, root: TreeNode | None) -> TreeNode | None:
+        if root is None:
+            return None
+
+        def dfs(c: TreeNode) -> TreeNode:
+            print(c)
+            val = c.val
+            left = c.left
+            right = c.right
+            new_right = None
+            new_left = None
+
+            if left:
+                new_right = dfs(left)
+            if right:
+                new_left = dfs(right)
+
+            return TreeNode(val, new_left, new_right)
+
+        return dfs(root)