mirror of
https://github.com/TheAlgorithms/Python.git
synced 2024-12-21 02:30:15 +00:00
bc8df6de31
* [pre-commit.ci] pre-commit autoupdate updates: - [github.com/astral-sh/ruff-pre-commit: v0.2.2 → v0.3.2](https://github.com/astral-sh/ruff-pre-commit/compare/v0.2.2...v0.3.2) - [github.com/pre-commit/mirrors-mypy: v1.8.0 → v1.9.0](https://github.com/pre-commit/mirrors-mypy/compare/v1.8.0...v1.9.0) * [pre-commit.ci] auto fixes from pre-commit.com hooks for more information, see https://pre-commit.ci --------- Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
89 lines
2.1 KiB
Python
89 lines
2.1 KiB
Python
"""
|
|
In a binary search tree (BST):
|
|
* The floor of key 'k' is the maximum value that is smaller than or equal to 'k'.
|
|
* The ceiling of key 'k' is the minimum value that is greater than or equal to 'k'.
|
|
|
|
Reference:
|
|
https://bit.ly/46uB0a2
|
|
|
|
Author : Arunkumar
|
|
Date : 14th October 2023
|
|
"""
|
|
|
|
from __future__ import annotations
|
|
|
|
from collections.abc import Iterator
|
|
from dataclasses import dataclass
|
|
|
|
|
|
@dataclass
|
|
class Node:
|
|
key: int
|
|
left: Node | None = None
|
|
right: Node | None = None
|
|
|
|
def __iter__(self) -> Iterator[int]:
|
|
if self.left:
|
|
yield from self.left
|
|
yield self.key
|
|
if self.right:
|
|
yield from self.right
|
|
|
|
def __len__(self) -> int:
|
|
return sum(1 for _ in self)
|
|
|
|
|
|
def floor_ceiling(root: Node | None, key: int) -> tuple[int | None, int | None]:
|
|
"""
|
|
Find the floor and ceiling values for a given key in a Binary Search Tree (BST).
|
|
|
|
Args:
|
|
root: The root of the binary search tree.
|
|
key: The key for which to find the floor and ceiling.
|
|
|
|
Returns:
|
|
A tuple containing the floor and ceiling values, respectively.
|
|
|
|
Examples:
|
|
>>> root = Node(10)
|
|
>>> root.left = Node(5)
|
|
>>> root.right = Node(20)
|
|
>>> root.left.left = Node(3)
|
|
>>> root.left.right = Node(7)
|
|
>>> root.right.left = Node(15)
|
|
>>> root.right.right = Node(25)
|
|
>>> tuple(root)
|
|
(3, 5, 7, 10, 15, 20, 25)
|
|
>>> floor_ceiling(root, 8)
|
|
(7, 10)
|
|
>>> floor_ceiling(root, 14)
|
|
(10, 15)
|
|
>>> floor_ceiling(root, -1)
|
|
(None, 3)
|
|
>>> floor_ceiling(root, 30)
|
|
(25, None)
|
|
"""
|
|
floor_val = None
|
|
ceiling_val = None
|
|
|
|
while root:
|
|
if root.key == key:
|
|
floor_val = root.key
|
|
ceiling_val = root.key
|
|
break
|
|
|
|
if key < root.key:
|
|
ceiling_val = root.key
|
|
root = root.left
|
|
else:
|
|
floor_val = root.key
|
|
root = root.right
|
|
|
|
return floor_val, ceiling_val
|
|
|
|
|
|
if __name__ == "__main__":
|
|
import doctest
|
|
|
|
doctest.testmod()
|