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Invert Binary Tree

Explore how to invert a binary tree by swapping each node's left and right subtrees recursively. Understand the process of creating a mirror image of a tree and gain practical experience solving this fundamental tree transformation problem.

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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:

  • 0≤0\leq Number of nodes in the tree ≤100\leq 100
  • −1000≤-1000 \leq Node.value ≤1000\leq 1000

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

1.

What is the correct mirrored tree for the given tree?

  5
 / \
6   7
   / \
  8   9
A.
  5
 / \
6   7
   / \
  8   9
B.
    5
   / \
  7   6
 / \  
9   8
C.
  5
 / \
6   7
   / \
  9   8
D.
  5
 / \
7   6
   / \
  9   8
1 / 2

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.

Sequence - Vertical
Drag and drop the cards to rearrange them in the correct sequence.
1
2
3

Try it yourself

Implement your solution in main.java in the following coding playground.

Java
usercode > Solution.java
// Definiton of a binary tree node class

// class TreeNode<T> {

//     T data;

//     TreeNode<T> left;

//     TreeNode<T> right;



//     TreeNode(T data) {

//         this.data = data;

//         this.left = null;

//         this.right = null;

//     }

// }



import java.util.*;

import ds_v1.BinaryTree.TreeNode;



public class Solution{



    public static TreeNode<Integer> invertTree(TreeNode<Integer> root){

       

       // Replace this placeholder return statement with your code

       return root; 

    }

}
Invert Binary Tree