0226 Invert Binary Tree

Solved at: 2022-07-26

Question

Given the root of a binary tree, invert the tree, and return its root.

Solution

# 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: Optional[TreeNode]) -> Optional[TreeNode]:
        if not root:
            return
        root.left, root.right = root.right, root.left
        if root.left:
            self.invertTree(root.left)
        if root.right:
            self.invertTree(root.right)
        return root

That was simple...

Results

Runtime

• 30 ms, faster than 95.71% of Python3 online submissions for Invert Binary Tree.

Memory Usage

• 13.9 MB, less than 11.66% of Python3 online submissions for Invert Binary Tree.

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