Easy
Quiz
#226 Invert Binary Tree
APPROACH
You are given the root of a binary tree. Produce a mirror image of it by recursively swapping every node's left and right children, then return the root.
Example 1:
Input: root = [4,2,7,1,3,6,9]
Output: [4,7,2,9,6,3,1]
Example 2:
Input: root = [2,1,3]
Output: [2,3,1]
Example 3:
Input: root = []
Output: []
1 of 4
1:00
What is the optimal approach for this problem?