class Node:
def __init__(self, data):
self.data = data
self.next = None
class LinkedList:
def __init__(self, node=None):
self.__head = node
def is_empty(self):
"""链表是否为空"""
return self.__head == None
def length(self):
"""链表长度"""
cur = self.__head
count = 0
while cur != None:
count += 1
cur = cur.next
return count
def travel(self):
"""遍历链表"""
cur = self.__head
while cur != None:
print(cur.data)
cur = cur.next
return
def add(self, item):
"""链表头部新增节点"""
node = Node(item)
node.next = self.__head
self.__head = node
def push(self, item):
"""链表尾部push节点"""
node = Node(item)
cur = self.__head
if not cur:
self.__head = node
return
while cur.next != None:
cur = cur.next
cur.next = node
def insert(self, pos, item):
"""链表中间插入节点"""
if pos <= 0:
self.add(item)
elif pos > self.length() - 1:
self.push(item)
else:
node = Node(item)
cur = self.__head
count = 0
while count < pos - 1:
count += 1
cur = cur.next
node.next = cur.next
cur.next = node
def remove(self, item):
"""链表删除指定元素"""
cur = self.__head
if cur.data == item:
self.__head = cur.next
return
while cur.next.data != item:
cur = cur.next
cur.next = cur.next.next
def search(self, pos):
"""链表查找指定序号元素"""
cur = self.__head
if not pos:
return cur
count = 0
while count != pos:
count += 1
cur = cur.next
return cur
