29 lines
485 B
Markdown
29 lines
485 B
Markdown
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## Unique Binary Search Trees
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Given `n`, how many structurally unique **BST's** (binary search trees) that store values 1 ... `n`?
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### Examples
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```text
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Input: 3
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Output: 5
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Explanation:
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Given n = 3, there are a total of 5 unique BST's:
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1 3 3 2 1
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\ / / / \ \
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3 2 1 1 3 2
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/ / \ \
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2 1 2 3
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```
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### Constraints
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- `1 <= n <= 19`
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---
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### Notes
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- N/A
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