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 0104. Maximum Depth 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::*0104. Maximum Depth of Binary Tree][0104. Maximum Depth 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 /its maximum depth/.
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A binary tree's *maximum depth* is the number of nodes along the longest path from the root node down to the farthest leaf node.
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*Example 1:*
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#+begin_src
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Input: root = [3,9,20,null,null,15,7]
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Output: 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,null,2]
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Output: 2
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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 ~[0, 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 maxDepth(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 maxDepth(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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