Python单链表的简单实现方法

本文实例讲述了python单链表的简单实现方法，分享给大家供大家参考。具体方法如下：

通常来说，要定义一个单链表,首先定义链表元素:element.它包含3个字段:

list:标识自己属于哪一个list
datum:改元素的value
next:下一个节点的位置

具体实现代码如下：

class linkedlist(object):
  
  class element(object):
    
    def __init__(self,list,datum,next): 
      self._list = list
      self._datum = datum 
      self._next = next

    def getdatum(self): 
      return self._datum

    datum = property(
      fget = lambda self: self.getdatum())

    def getnext(self):
      return self._next

    next = property(
      fget = lambda self: self.getnext())

  def __init__(self):

    self._head = none
    self._tail = none
  def gethead(self):
    return self._head 
  head = property(
    fget = lambda self: self.gethead()) 
  def prepend(self,item):
    tmp = self.element (self,item,self._head)
    if self._head is none:
      self._tail = tmp 
    self._head = tmp 

  def insert(self, pos, item):
    i = 0
    p = self._head
    while p != none and i < pos -1:
      p = p._next
      i += 1
    if p == none or i > pos-1:
      return -1
    tmp = self.element(self, item, p._next)
    p._next = tmp
    return 1
  def getitem(self, pos):
    i = 0
    p = self._head
    while p != none and i < pos -1:
      p = p._next
      i += 1
    if p == none or i > post-1:
      return -1
    return p._datum
  def delete(self, pos):
    i = 0
    p = self._head
    while p != none and i < pos -1:
      p = p._next
      i += 1
    if p == none or i > post-1:
      return -1
    q = p._next
    p._nex = q._next
    datum = p._datum
    return datum
  def setitem(self, pos, item):
    i = 0
    p = self._head
    while p != none and i < pos -1:
      p = p._next
      i += 1
    if p == none or i > post-1:
      return -1
    p._datum = item
    return 1
  def find(self, pos, item):
    i = 0
    p = self._head
    while p != none and i < pos -1:
      if p._datum == item:
        return 1
      p = p._next
      i += 1
    return -1
  def empty(self):
    if self._head == none:
      return 1
    return 0
  def size(self):
    i = 0
    p = self._head
    while p != none and i < pos -1:
      p = p._next
      i += 1
    return i

  def clear(self):
    self._head = none
    self._tail = none

test = linkedlist()
test.prepend('test0')
print test.insert(1, 'test')
print test.head.datum
print test.head.next.datum

希望本文所述对大家的python程序设计有所帮助。