This commit is contained in:
krahets
2023-04-09 05:12:22 +08:00
parent 01d05cc1f0
commit 37f11aff68
27 changed files with 265 additions and 248 deletions

View File

@@ -591,31 +591,33 @@ comments: true
```python title="linkedlist_deque.py"
class ListNode:
""" 双向链表节点 """
"""双向链表节点"""
def __init__(self, val: int) -> None:
""" 构造方法 """
"""构造方法"""
self.val: int = val
self.next: ListNode | None = None # 后继节点引用(指针)
self.prev: ListNode | None = None # 前驱节点引用(指针)
class LinkedListDeque:
""" 基于双向链表实现的双向队列 """
"""基于双向链表实现的双向队列"""
def __init__(self) -> None:
""" 构造方法 """
self.front: ListNode | None = None # 头节点 front
"""构造方法"""
self.front: ListNode | None = None # 头节点 front
self.rear: ListNode | None = None # 尾节点 rear
self.__size: int = 0 # 双向队列的长度
self.__size: int = 0 # 双向队列的长度
def size(self) -> int:
""" 获取双向队列的长度 """
"""获取双向队列的长度"""
return self.__size
def is_empty(self) -> bool:
""" 判断双向队列是否为空 """
"""判断双向队列是否为空"""
return self.size() == 0
def push(self, num: int, is_front: bool) -> None:
""" 入队操作 """
"""入队操作"""
node = ListNode(num)
# 若链表为空,则令 front, rear 都指向 node
if self.is_empty():
@@ -635,15 +637,15 @@ comments: true
self.__size += 1 # 更新队列长度
def push_first(self, num: int) -> None:
""" 队首入队 """
"""队首入队"""
self.push(num, True)
def push_last(self, num: int) -> None:
""" 队尾入队 """
"""队尾入队"""
self.push(num, False)
def pop(self, is_front: bool) -> int:
""" 出队操作 """
"""出队操作"""
# 若队列为空,直接返回 None
if self.is_empty():
return None
@@ -669,23 +671,23 @@ comments: true
return val
def pop_first(self) -> int:
""" 队首出队 """
"""队首出队"""
return self.pop(True)
def pop_last(self) -> int:
""" 队尾出队 """
"""队尾出队"""
return self.pop(False)
def peek_first(self) -> int:
""" 访问队首元素 """
"""访问队首元素"""
return None if self.is_empty() else self.front.val
def peek_last(self) -> int:
""" 访问队尾元素 """
"""访问队尾元素"""
return None if self.is_empty() else self.rear.val
def to_array(self) -> list[int]:
""" 返回数组用于打印 """
"""返回数组用于打印"""
node: ListNode | None = self.front
res: list[int] = [0] * self.size()
for i in range(self.size()):
@@ -1583,34 +1585,35 @@ comments: true
```python title="array_deque.py"
class ArrayDeque:
""" 基于环形数组实现的双向队列 """
"""基于环形数组实现的双向队列"""
def __init__(self, capacity: int) -> None:
""" 构造方法 """
"""构造方法"""
self.__nums: list[int] = [0] * capacity
self.__front: int = 0
self.__size: int = 0
def capacity(self) -> int:
""" 获取双向队列的容量 """
"""获取双向队列的容量"""
return len(self.__nums)
def size(self) -> int:
""" 获取双向队列的长度 """
"""获取双向队列的长度"""
return self.__size
def is_empty(self) -> bool:
""" 判断双向队列是否为空 """
"""判断双向队列是否为空"""
return self.__size == 0
def index(self, i: int) -> int:
""" 计算环形数组索引 """
"""计算环形数组索引"""
# 通过取余操作实现数组首尾相连
# 当 i 越过数组尾部后,回到头部
# 当 i 越过数组头部后,回到尾部
return (i + self.capacity()) % self.capacity()
def push_first(self, num: int) -> None:
""" 队首入队 """
"""队首入队"""
if self.__size == self.capacity():
print("双向队列已满")
return
@@ -1622,7 +1625,7 @@ comments: true
self.__size += 1
def push_last(self, num: int) -> None:
""" 队尾入队 """
"""队尾入队"""
if self.__size == self.capacity():
print("双向队列已满")
return
@@ -1633,7 +1636,7 @@ comments: true
self.__size += 1
def pop_first(self) -> int:
""" 队首出队 """
"""队首出队"""
num = self.peek_first()
# 队首指针向后移动一位
self.__front = self.index(self.__front + 1)
@@ -1641,25 +1644,25 @@ comments: true
return num
def pop_last(self) -> int:
""" 队尾出队 """
"""队尾出队"""
num = self.peek_last()
self.__size -= 1
return num
def peek_first(self) -> int:
""" 访问队首元素 """
"""访问队首元素"""
assert not self.is_empty(), "双向队列为空"
return self.__nums[self.__front]
def peek_last(self) -> int:
""" 访问队尾元素 """
"""访问队尾元素"""
assert not self.is_empty(), "双向队列为空"
# 计算尾元素索引
last = self.index(self.__front + self.__size - 1)
return self.__nums[last]
def to_array(self) -> list[int]:
""" 返回数组用于打印 """
"""返回数组用于打印"""
# 仅转换有效长度范围内的列表元素
res = []
for i in range(self.__size):