def append(self, elem):
if self._head is None:
self._head = LNode(elem)
self._rear = self._head
else:
self._rear.next_ = LNode(elem)
self._rear = self._rear.next_
def prepend(self, elem):
p = LNode(elem)
if self._rear is None:
p.next = p
self._rear = p
else:
p.next = self._rear.next
self._rear.next = p
def prepend(self, elem):
# 把要插入的数据放入一个结点
p = LNode(elem)
# 如果是空表，建立循环
if self._rear is None:
p.next = p
self._rear = p
else:
p.next = self._rear.next
self._rear.next = p
def append(self, elem):
# 如果是空表
if self._head is None:
self._head = LNode(elem, self._head)
self._rear = self._head
else:
# 先让尾结点的引用域指向新增加的结点
# 再让尾结点指针指向新的结点
self._rear.next = LNode(elem)
self._rear = self._rear.next
def prepend(self, elem):
if self._head is None: # 如果是空表
# LNode(elem, self._head) - 先让新结点的引用域指向原来头指针指向的地方
# 再让头指针指向新的结点
self._head = LNode(elem, self._head)
# 头指针和尾结点的指针都指向新的结点
self._rear = self._head
# 不是空表
else:
self._head = LNode(elem, self._head)
def insert(self, elem, i=0):
p = self._head
if i == 0:
if self._head is None:
self._head = LNode(elem, self._head)
self._rear = self._head
else:
self._head = LNode(elem, self._head)
return
elif i != 0 and self._head is None:
raise LinkedListUnderflow("insert")
elif self.length() < i or i < 0:
raise LinkedListUnderflow("insert length error")
else:
pass
while p is not None and (i - 1) > 0:
i -= 1
p = p.next
p.next = LNode(elem, p.next)
self._rear = p.next
def prepend(self, elem):
if self._head is None:
self._head = LNode(elem)
self._rear = self._head
else:
self._head = LNode(elem, self._head)
def __init__(self, elem, prev=None, next_=None):
LNode.__init__(self, elem, next_)
self.prev = prev