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Diameter of Binary Tree

Detailed guide and Python implementation for the 'Diameter of Binary Tree' problem.

Problem Statement

Medium

Given the root of a binary tree, return the length of the diameter of the tree.

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.

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

The tree is represented as a level-order list. Implement a function diameterOfBinaryTree(root: list) -> int.

Constraints
  • The number of nodes in the tree is in the range [1, 10000]
  • -100 <= Node.val <= 100

Examples

Example 1
Input
[1,2,3,4,5]
Output
3
Explanation

The longest path is 4->2->1->3 or 5->2->1->3, which has 3 edges.

Example 2
Input
[1,2]
Output
1
Explanation

The longest path is 2->1, which has 1 edge.

Need a Hint?
Consider using Trees-specific data structures like sets or heaps.
Edge Cases to Watch
  • Empty input structures
  • Single element inputs
  • Large numerical bounds

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