以下是三个类:节点,双向链表和在双向链表上实现的排序列表。这是我的代码:
class DLLNode(object):
def __Init__ (self, data, prev_node=None, next_node=None):
self.data=data
self.prev_node=prev_node
self.next_node=next_node
def __str__(self):
return str(self.data)
class DoublyLinkedList(object):
def __init__(self, head=None, tail=None):
self.head=head
self.tail=tail
self.size=0
def add_to_head(self, data):
newNode = DLLNode(data)
if self.head==None:
self.head=self.tail=newNode
self.head.prev_node=self.tail.next_node=None
else:
self.head.prev_node=newNode
newNode.next_node=self.head
self.head=newNode
def add_to_tail(self, data):
newNode=DLLNode(data)
if self.head==None:
self.head=self.tail=newNode
self.head.prev_node=self.tail.next_node=None
else:
self.tail.next_node=newNode
newNode.prev_node=self.tail
self.tail=newNode
self.tail.next_node=None
def remove_head(self):
node=self.head
if self.head==self.tail:
self.prev_node=self.next_node=self.head=self.tail=None
return
if self.head!=self.tail:
node=node.next_node
node.prev_node=None
self.head=node
def remove_tail(self):
node=self.tail
if self.head==self.tail:
self.prev_node=self.next_node=self.head=self.tail=None
return
if self.head!=self.tail:
self.tail=node.prev_node
self.tail.next_node=None
def index(self,element):
current = self.head
while current != None:
if current.data == element:
return current.position
else:
current = current.next
return -1
class SortedList(object):
def __init__(self, sequence = []):
if len(sequence)==0:
self.head = None
self.tail = None
else:
cur_node = None
prev_node = None
sequence.sort()
sequence.reverse()
for element in sequence:
prev_node = cur_node
cur_node = DLLNode(element, cur_node, prev_node)
self.head = cur_node
self.tail = DLLNode(sequence[0])
对于排序列表类,我需要创建一个添加和删除功能。但是,我真的不知道该怎么做。有人能告诉我吗?