#!/usr/bin/python
# -*- coding: utf-8 -*-
#change1
#change2
#change3
class Node(object):
def __init__(self, val, p=0):
self.data = val
self.next = p
class LinkList(object):
def __init__(self):
self.head = 0
def __getitem__(self, key):
if self.is_empty():
print 'linklist is empty.'
return
elif key < 0 or key > self.getlength():
print 'the given key is error'
return
else:
return self.getitem(key)
def __setitem__(self, key, value):
if self.is_empty():
print 'linklist is empty.'
return
elif key < 0 or key > self.getlength():
print 'the given key is error'
return
else:
self.delete(key)
return self.insert(key)
def initlist(self, data):
self.head = Node(data[0])
p = self.head
for i in data[1:]:
node = Node(i)
p.next = node
p = p.next
def getlength(self):
p = self.head
length = 0
while p != 0:
length += 1
p = p.next
return length
def is_empty(self):
if self.getlength() == 0:
return True
else:
return False
def clear(self):
self.head = 0
def append(self, item):
q = Node(item)
if self.head == 0:
self.head = q
else:
p = self.head
while p.next != 0:
p = p.next
p.next = q
def getitem(self, index):
if self.is_empty():
print 'Linklist is empty.'
return
j = 0
p = self.head
while p.next != 0 and j < index:
p = p.next
j += 1
if j == index:
return p.data
else:
print 'target is not exist!'
def insert(self, index, item):
if self.is_empty() or index < 0 or index > self.getlength():
print 'Linklist is empty.'
return
if index == 0:
q = Node(item, self.head)
self.head = q
p = self.head
post = self.head
j = 0
while p.next != 0 and j < index:
post = p
p = p.next
j += 1
if index == j:
q = Node(item, p)
post.next = q
q.next = p
def delete(self, index):
if self.is_empty() or index < 0 or index > self.getlength():
print 'Linklist is empty.'
return
if index == 0:
q = Node(item, self.head)
self.head = q
p = self.head
post = self.head
j = 0
while p.next != 0 and j < index:
post = p
p = p.next
j += 1
if index == j:
post.next = p.next
def index(self, value):
if self.is_empty():
print 'Linklist is empty.'
return
p = self.head
i = 0
while p.next != 0 and not p.data == value:
p = p.next
i += 1
if p.data == value:
return i
else:
return -1
l = LinkList()
l.initlist([1, 2, 3, 4, 5])
print l.getitem(4)
l.append(6)
print l.getitem(5)
l.insert(4, 40)
print l.getitem(3)
print l.getitem(4)
print l.getitem(5)
l.delete(5)
print l.getitem(5)
l.index(5)