Invert Binary Tree
Explore how to invert a binary tree by swapping each node’s left and right children using depth-first search. This lesson helps you understand the problem constraints, develop a clear algorithmic approach, and implement the solution in JavaScript, strengthening your coding interview skills.
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Statement
Given the root node of a binary tree, transform the tree by swapping each node’s left and right subtrees, thus creating a mirror image of the original tree. Return the root of the transformed tree.
Constraints:
- Number of nodes in the tree
-
Node.value
Examples
Understand the problem
Let’s take a moment to make sure you’ve correctly understood the problem. The quiz below helps you check if you’re solving the correct problem:
Invert Binary Tree
What is the correct mirrored tree for the given tree?
5
/ \
6 7
/ \
8 9
5
/ \
6 7
/ \
8 9
5
/ \
7 6
/ \
9 8
5
/ \
6 7
/ \
9 8
5
/ \
7 6
/ \
9 8
Figure it out!
We have a game for you to play. Rearrange the logical building blocks to develop a clearer understanding of how to solve this problem.
Try it yourself
Implement your solution in main.js in the following coding playground.
// Definition of a binary tree node// class TreeNode {// constructor(data) {// this.data = data;// this.left = null;// this.right = null;// }// }import {TreeNode} from './ds_v1/BinaryTree.js';function mirrorBinaryTree(root) {// Replace this placeholder return statement with your codereturn root;}export{ mirrorBinaryTree };