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Diameter of Binary Tree

Explore how to calculate the diameter of a binary tree by identifying the longest path between any two nodes. This lesson helps you understand tree structures using depth-first search to solve binary tree problems effectively. You will practice implementing and optimizing your solution within given constraints.

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Statement

Given a binary tree, you need to compute the length of the tree’s diameter. The diameter of a binary tree is the length of the longest path between any two nodes in a tree. This path may or may not pass through the root.

Note: The length of the path between two nodes is represented by the number of edges between them.

Constraints:

  • The number of nodes in the tree is in the range [1,500][1, 500].
  • −100≤-100 \leq Node.value ≤100\leq 100

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:

Diameter of Binary Tree

1.

What is the diameter of the following binary tree?

  5
 / \
6   7
   / \
  8   9
A.

2

B.

3

C.

4

D.

5

1 / 4

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
4

Try it yourself

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

Java
usercode > Solution.java
import java.util.*;

import ds_v1.BinaryTree.TreeNode;



// 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;

//     }

// }



public class Solution{

    public static int diameterOfBinaryTree(TreeNode<Integer> root) {



    // Replace this placeholder return statement with your code

    return -1;

  }

}
Diameter of Binary Tree