59 lines
1.2 KiB
Markdown
59 lines
1.2 KiB
Markdown
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---
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layout: page
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title: Convert Sorted Array to Binary Search Tree
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last_solved:
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category:
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leetcode_url: https://leetcode.com/problems/convert-sorted-array-to-binary-search-tree/
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status: Attempted
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---
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Problem
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-------
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```
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Given an array where elements are sorted in ascending order, convert it to a height balanced BST.
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For this problem, a height-balanced binary tree is defined as a binary tree in which the depth of the two subtrees of every node never differ by more than 1.
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Example:
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Given the sorted array: [-10,-3,0,5,9],
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One possible answer is: [0,-3,9,-10,null,5], which represents the following height balanced BST:
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0
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/ \
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-3 9
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/ /
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-10 5
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```
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Solution
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----------
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{% highlight python %}
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def sortedArrayToBST(self, nums: List[int]) -> TreeNode:
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def buildTree(nums, left, right):
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if left>right: return
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mid = (left+right) // 2
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node = TreeNode(nums[mid])
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node.left = buildTree(nums, left, mid-1)
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node.right = buildTree(nums, mid+1, right)
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return node
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if not nums: return None
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return buildTree(nums, 0, len(nums)-1)
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{% endhighlight %}
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![image1]()
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