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Update code style for Python

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krahets
2023-03-03 03:07:22 +08:00
parent 7e9e6b000c
commit 7c501140f0
45 changed files with 274 additions and 266 deletions
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29
codes/python/chapter_tree/avl_tree.py
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@ -6,35 +6,36 @@ Author: a16su (lpluls001@gmail.com)
import sys, os.path as osp
sys.path.append(osp.dirname(osp.dirname(osp.abspath(__file__))))
from include import *
from modules import *
""" AVL 树 """
class AVLTree:
""" AVL 树 """
def __init__(self, root: Optional[TreeNode] = None):
""" 构造方法 """
self.root = root
""" 获取结点高度 """
def height(self, node: Optional[TreeNode]) -> int:
""" 获取结点高度 """
# 空结点高度为 -1 ，叶结点高度为 0
if node is not None:
return node.height
return -1
""" 更新结点高度 """
def __update_height(self, node: Optional[TreeNode]):
""" 更新结点高度 """
# 结点高度等于最高子树高度 + 1
node.height = max([self.height(node.left), self.height(node.right)]) + 1
""" 获取平衡因子 """
def balance_factor(self, node: Optional[TreeNode]) -> int:
""" 获取平衡因子 """
# 空结点平衡因子为 0
if node is None:
return 0
# 结点平衡因子 = 左子树高度 - 右子树高度
return self.height(node.left) - self.height(node.right)
""" 右旋操作 """
def __right_rotate(self, node: Optional[TreeNode]) -> TreeNode:
""" 右旋操作 """
child = node.left
grand_child = child.right
# 以 child 为原点，将 node 向右旋转
@ -46,8 +47,8 @@ class AVLTree:
# 返回旋转后子树的根结点
return child
""" 左旋操作 """
def __left_rotate(self, node: Optional[TreeNode]) -> TreeNode:
""" 左旋操作 """
child = node.right
grand_child = child.left
# 以 child 为原点，将 node 向左旋转
@ -59,8 +60,8 @@ class AVLTree:
# 返回旋转后子树的根结点
return child
""" 执行旋转操作，使该子树重新恢复平衡 """
def __rotate(self, node: Optional[TreeNode]) -> TreeNode:
""" 执行旋转操作，使该子树重新恢复平衡 """
# 获取结点 node 的平衡因子
balance_factor = self.balance_factor(node)
# 左偏树
@ -84,13 +85,13 @@ class AVLTree:
# 平衡树，无需旋转，直接返回
return node
""" 插入结点 """
def insert(self, val) -> TreeNode:
""" 插入结点 """
self.root = self.__insert_helper(self.root, val)
return self.root
""" 递归插入结点（辅助方法）"""
def __insert_helper(self, node: Optional[TreeNode], val: int) -> TreeNode:
""" 递归插入结点（辅助方法）"""
if node is None:
return TreeNode(val)
# 1. 查找插入位置，并插入结点
@ -106,13 +107,13 @@ class AVLTree:
# 2. 执行旋转操作，使该子树重新恢复平衡
return self.__rotate(node)
""" 删除结点 """
def remove(self, val: int):
""" 删除结点 """
root = self.__remove_helper(self.root, val)
return root
""" 递归删除结点（辅助方法） """
def __remove_helper(self, node: Optional[TreeNode], val: int) -> Optional[TreeNode]:
""" 递归删除结点（辅助方法） """
if node is None:
return None
# 1. 查找结点，并删除之
@ -138,8 +139,8 @@ class AVLTree:
# 2. 执行旋转操作，使该子树重新恢复平衡
return self.__rotate(node)
""" 获取中序遍历中的下一个结点（仅适用于 root 有左子结点的情况） """
def __get_inorder_next(self, node: Optional[TreeNode]) -> Optional[TreeNode]:
""" 获取中序遍历中的下一个结点（仅适用于 root 有左子结点的情况） """
if node is None:
return None
# 循环访问左子结点，直到叶结点时为最小结点，跳出
@ -147,8 +148,8 @@ class AVLTree:
node = node.left
return node
""" 查找结点 """
def search(self, val: int):
""" 查找结点 """
cur = self.root
# 循环查找，越过叶结点后跳出
while cur is not None: