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krahets
2023-03-12 18:46:03 +08:00
parent 209d82a8cc
commit f6b9a75c8f
23 changed files with 406 additions and 359 deletions
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40
chapter_tree/avl_tree.md
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@@ -35,9 +35,9 @@ G. M. Adelson-Velsky 和 E. M. Landis 在其 1962 年发表的论文 "An algorit
```java title=""
/* AVL 树结点类 */
class TreeNode {
public int val; // 结点值
public int height; // 结点高度
public TreeNode left; // 左子结点
public int val; // 结点值
public int height; // 结点高度
public TreeNode left; // 左子结点
public TreeNode right; // 右子结点
public TreeNode(int x) { val = x; }
}
@@ -48,10 +48,10 @@ G. M. Adelson-Velsky 和 E. M. Landis 在其 1962 年发表的论文 "An algorit
```cpp title=""
/* AVL 树结点类 */
struct TreeNode {
int val{}; // 结点值
int height = 0; // 结点高度
TreeNode *left{}; // 左子结点
TreeNode *right{}; // 右子结点
int val{}; // 结点值
int height = 0; // 结点高度
TreeNode *left{}; // 左子结点
TreeNode *right{}; // 右子结点
TreeNode() = default;
explicit TreeNode(int x) : val(x){}
};
@@ -62,11 +62,11 @@ G. M. Adelson-Velsky 和 E. M. Landis 在其 1962 年发表的论文 "An algorit
```python title=""
""" AVL 树结点类 """
class TreeNode:
def __init__(self, val=None, left=None, right=None):
self.val = val # 结点值
self.height = 0 # 结点高度
self.left = left # 左子结点引用
self.right = right # 右子结点引用
def __init__(self, val: int):
self.val: int = val # 结点值
self.height: int = 0 # 结点高度
self.left: Optional[TreeNode] = None # 左子结点引用
self.right: Optional[TreeNode] = None # 右子结点引用
```
=== "Go"
@@ -517,7 +517,7 @@ AVL 树的独特之处在于「旋转 Rotation」的操作，其可 **在不影
=== "Python"
```python title="avl_tree.py"
def __right_rotate(self, node: Optional[TreeNode]) -> TreeNode:
def __right_rotate(self, node: Optional[TreeNode]) -> Optional[TreeNode]:
""" 右旋操作 """
child = node.left
grand_child = child.right
@@ -701,7 +701,7 @@ AVL 树的独特之处在于「旋转 Rotation」的操作，其可 **在不影
=== "Python"
```python title="avl_tree.py"
def __left_rotate(self, node: Optional[TreeNode]) -> TreeNode:
def __left_rotate(self, node: Optional[TreeNode]) -> Optional[TreeNode]:
""" 左旋操作 """
child = node.right
grand_child = child.left
@@ -940,7 +940,7 @@ AVL 树的独特之处在于「旋转 Rotation」的操作，其可 **在不影
=== "Python"
```python title="avl_tree.py"
def __rotate(self, node: Optional[TreeNode]) -> TreeNode:
def __rotate(self, node: Optional[TreeNode]) -> Optional[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)
@@ -1251,8 +1251,8 @@ AVL 树的独特之处在于「旋转 Rotation」的操作，其可 **在不影
```python title="avl_tree.py"
def insert(self, val) -> TreeNode:
""" 插入结点 """
self.root = self.__insert_helper(self.root, val)
return self.root
self.__root = self.__insert_helper(self.__root, val)
return self.__root
def __insert_helper(self, node: Optional[TreeNode], val: int) -> TreeNode:
""" 递归插入结点（辅助方法）"""
@@ -1571,10 +1571,10 @@ AVL 树的独特之处在于「旋转 Rotation」的操作，其可 **在不影
=== "Python"
```python title="avl_tree.py"
def remove(self, val: int):
def remove(self, val: int) -> Optional[TreeNode]:
""" 删除结点 """
root = self.__remove_helper(self.root, val)
return root
self.__root = self.__remove_helper(self.__root, val)
return self.__root
def __remove_helper(self, node: Optional[TreeNode], val: int) -> Optional[TreeNode]:
""" 递归删除结点（辅助方法） """

16
chapter_tree/binary_search_tree.md
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@@ -82,7 +82,7 @@ comments: true
```python title="binary_search_tree.py"
def search(self, num: int) -> Optional[TreeNode]:
""" 查找结点 """
cur = self.root
cur: Optional[TreeNode] = self.__root
# 循环查找，越过叶结点后跳出
while cur is not None:
# 目标结点在 cur 的右子树中
@@ -310,13 +310,12 @@ comments: true
```python title="binary_search_tree.py"
def insert(self, num: int) -> Optional[TreeNode]:
""" 插入结点 """
root = self.root
# 若树为空，直接提前返回
if root is None:
if self.__root is None:
return None
# 循环查找，越过叶结点后跳出
cur, pre = root, None
cur, pre = self.__root, None
while cur is not None:
# 找到重复结点，直接返回
if cur.val == num:
@@ -694,13 +693,12 @@ comments: true
```python title="binary_search_tree.py"
def remove(self, num: int) -> Optional[TreeNode]:
""" 删除结点 """
root = self.root
# 若树为空，直接提前返回
if root is None:
if self.__root is None:
return None
# 循环查找，越过叶结点后跳出
cur, pre = root, None
cur, pre = self.__root, None
while cur is not None:
# 找到待删除结点，跳出循环
if cur.val == num:
@@ -726,8 +724,8 @@ comments: true
# 子结点数量 = 2
else:
# 获取中序遍历中 cur 的下一个结点
nex = self.get_inorder_next(cur.right)
tmp = nex.val
nex: TreeNode = self.get_inorder_next(cur.right)
tmp: int = nex.val
# 递归删除结点 nex
self.remove(nex.val)
# 将 nex 的值复制给 cur

24
chapter_tree/binary_tree.md
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@@ -9,7 +9,7 @@ comments: true
=== "Java"
```java title=""
/* 链表结点类 */
/* 二叉树结点类 */
class TreeNode {
int val; // 结点值
TreeNode left; // 左子结点指针
@@ -21,7 +21,7 @@ comments: true
=== "C++"
```cpp title=""
/* 链表结点结构体 */
/* 二叉树结点结构体 */
struct TreeNode {
int val; // 结点值
TreeNode *left; // 左子结点指针
@@ -33,18 +33,18 @@ comments: true
=== "Python"
```python title=""
""" 链表结点类 """
""" 二叉树结点类 """
class TreeNode:
def __init__(self, val=None, left=None, right=None):
self.val = val # 结点值
self.left = left # 左子结点指针
self.right = right # 右子结点指针
def __init__(self, val: int):
self.val: int = val # 结点值
self.left: Optional[TreeNode] = None # 左子结点指针
self.right: Optional[TreeNode] = None # 右子结点指针
```
=== "Go"
```go title=""
/* 链表结点结构体 */
/* 二叉树结点结构体 */
type TreeNode struct {
Val int
Left *TreeNode
@@ -63,7 +63,7 @@ comments: true
=== "JavaScript"
```javascript title=""
/* 链表结点类 */
/* 二叉树结点类 */
function TreeNode(val, left, right) {
this.val = (val === undefined ? 0 : val); // 结点值
this.left = (left === undefined ? null : left); // 左子结点指针
@@ -74,7 +74,7 @@ comments: true
=== "TypeScript"
```typescript title=""
/* 链表结点类 */
/* 二叉树结点类 */
class TreeNode {
val: number;
left: TreeNode | null;
@@ -97,7 +97,7 @@ comments: true
=== "C#"
```csharp title=""
/* 链表结点类 */
/* 二叉树结点类 */
class TreeNode {
int val; // 结点值
TreeNode? left; // 左子结点指针
@@ -109,7 +109,7 @@ comments: true
=== "Swift"
```swift title=""
/* 链表结点类 */
/* 二叉树结点类 */
class TreeNode {
var val: Int // 结点值
var left: TreeNode? // 左子结点指针

20
chapter_tree/binary_tree_traversal.md
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@@ -69,20 +69,20 @@ comments: true
=== "Python"
```python title="binary_tree_bfs.py"
def level_order(root: Optional[TreeNode]):
def level_order(root: Optional[TreeNode]) -> List[int]:
""" 层序遍历 """
# 初始化队列，加入根结点
queue = collections.deque()
queue: Deque[TreeNode] = collections.deque()
queue.append(root)
# 初始化一个列表，用于保存遍历序列
res = []
res: List[int] = []
while queue:
node = queue.popleft() # 队列出队
res.append(node.val) # 保存结点值
node: TreeNode = queue.popleft() # 队列出队
res.append(node.val) # 保存结点值
if node.left is not None:
queue.append(node.left) # 左子结点入队
queue.append(node.left) # 左子结点入队
if node.right is not None:
queue.append(node.right) # 右子结点入队
queue.append(node.right) # 右子结点入队
return res
```
@@ -337,7 +337,7 @@ comments: true
=== "Python"
```python title="binary_tree_dfs.py"
def pre_order(root: Optional[TreeNode]):
def pre_order(root: Optional[TreeNode]) -> None:
""" 前序遍历 """
if root is None:
return
@@ -346,7 +346,7 @@ comments: true
pre_order(root=root.left)
pre_order(root=root.right)
def in_order(root: Optional[TreeNode]):
def in_order(root: Optional[TreeNode]) -> None:
""" 中序遍历 """
if root is None:
return
@@ -355,7 +355,7 @@ comments: true
res.append(root.val)
in_order(root=root.right)
def post_order(root: Optional[TreeNode]):
def post_order(root: Optional[TreeNode]) -> None:
""" 后序遍历 """
if root is None:
return