python实现链表

刚学不久python,来实现一下单链表

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网上拉的图：

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下面是代码了：

#!/usr/bin/python
# -*- coding: utf-8 -*-

#__author__ = 'Mr Cai'

class Node(object):
    '''节点'''

    def __init__(self,val,p = 0):
        self.data = val
        self.next = p


class LinkList(object):
    '''单链表类'''

    def __init__(self):
        self.head = 0


    def initlist (self,data):
        '''初始化列表'''

        #创建头节点，next为0
        self.head = Node(data[0])

        p = self.head
        for item in data[1:]:
            node = Node(item)
            p.next = node
            p = node


    def getlength(self):
        '''获取链表长度'''

        if self.head == 0:
            return  0

        p = self.head
        length = 1
        while p.next != 0:
            p = p.next
            length += 1

        return  length


    def IsEmpty(self):
        '''判断链表是否是空，布尔型'''

        if self.head == 0:
            return  True
        else:
            return  False

    def clear(self):
        '''清空列表'''

        self.head = 0


    def append(self,item):
        '''尾部加入元素'''

        if self.head == 0:
            self.head = Node(item)

        p = self.head
        while p.next != 0:
            p = p.next

        node = Node(item)
        p.next = node

    def getitem(self,index):
        '''给位置，打印元素'''

        if self.IsEmpty() :
            print 'The List is empty!'
            return

        if index < 0 or index > self.getlength() :
            print 'The index is error!'
            return

        p = self.head
        for i in range(0,index):
            p = p.next

        print p.data


    def insert(self,item,index):
        '''插入元素'''

        if self.IsEmpty():
            print 'The list is empty'
            return

        if index < 0 or index > self.getlength() :
            print 'The index is error!'
            return

        p = self.head
        for i in range(0,index - 1):
            p = p.next

        temp = p.next
        node = Node(item,temp)
        p.next = node


    def delete(self,index):
        '''删除元素'''

        if self.IsEmpty():
            print 'The list is empty'
            return

        if index < 0 or index > self.getlength() :
            print 'The index is error!'
            return

        p = self.head
        for i in range(0,index - 1):
            p = p.next
        p.next = p.next.next

    def show(self):
        '''打印出当前链表中所有元素'''
        if self.IsEmpty():
            print 'The list is empty'
            return

        p = self.head
        while p != 0 :
            print p.data
            p = p.next

if __name__ == '__main__' :

    List = LinkList()
    print List.IsEmpty()
    List.initlist([3,5,6,8])
    # List.show()
    List.append(10)
    # List.show()
    # print List.getlength()
    # List.clear()
    # List.show()
    # List.insert(111,3)
    # List.show()
    # List.delete(2)
    # List.show()