28 lines
753 B
Python
28 lines
753 B
Python
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# Time: O(N)
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# Space: O(N)
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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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maxDepthValue = 0
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def maxDepth(self, root: Optional[TreeNode]) -> int:
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'''
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Recursive DFS pre-order but storing max globally
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'''
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def findMax(node, depth):
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if node is None: return None
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currDepth = depth + 1
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self.maxDepthValue = max(currDepth, self.maxDepthValue)
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findMax(node.left, currDepth)
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findMax(node.right, currDepth)
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findMax(root, 0)
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return self.maxDepthValue
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