2026-06-01 16:12:21 +08:00
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#+PROPERTY: STUDY_DECK_02
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2026-06-01 17:12:10 +08:00
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* TODO 0543. Diameter of Binary Tree :easy:
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2026-06-01 02:33:30 +08:00
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:PROPERTIES:
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2026-06-01 17:22:07 +08:00
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:NEETCODE: [[file:../../roadmap.org::*0543. Diameter of Binary Tree][0543. Diameter of Binary Tree]]
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2026-06-01 02:33:30 +08:00
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:END:
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2026-06-01 17:22:07 +08:00
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Given the ~root~ of a binary tree, return /the length of the *diameter* of the tree/.
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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~.
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The *length* of a path between two nodes is represented by the number of edges between them.
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*Example 1:*
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#+begin_src
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Input: root = [1,2,3,4,5]
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Output: 3
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Explanation: 3 is the length of the path [4,2,1,3] or [5,2,1,3].
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#+end_src
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*Example 2:*
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#+begin_src
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Input: root = [1,2]
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Output: 1
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#+end_src
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*Constraints:*
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- The number of nodes in the tree is in the range ~[1, 10^{4}]~.
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- ~-100 <= Node.val <= 100~
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2026-06-01 02:39:53 +08:00
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** TODO Approach
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Write your approach here.
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** TODO Python
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#+begin_src python
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2026-06-01 17:22:07 +08:00
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# Definition for a binary tree node.
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# class TreeNode:
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# def __init__(self, val=0, left=None, right=None):
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# self.val = val
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# self.left = left
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# self.right = right
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class Solution:
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def diameterOfBinaryTree(self, root: Optional[TreeNode]) -> int:
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2026-06-01 02:39:53 +08:00
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#+end_src
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** TODO C++
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2026-06-01 02:33:30 +08:00
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#+begin_src cpp
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2026-06-01 17:22:07 +08:00
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/**
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* Definition for a binary tree node.
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* struct TreeNode {
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* int val;
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* TreeNode *left;
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* TreeNode *right;
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* TreeNode() : val(0), left(nullptr), right(nullptr) {}
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* TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
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* TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
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* };
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*/
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class Solution {
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public:
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int diameterOfBinaryTree(TreeNode* root) {
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}
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};
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2026-06-01 02:33:30 +08:00
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#+end_src
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