最近在学习python, 学起来很不错，在我一个初学者的眼中，这是一门很好的脚本语言。无论学习者有没有编程经验，都可以很好的学习。当然，要想学好，做练习是必不可少的。一些简单的练习，我就不再说了。在这里，我想从学习新语言的同时，正好把忘了的数据结构好好补补。因此，现在我准备实现一个hashmap，只是完成最基础的功能。毕竟，本人也是菜鸟一个，如果写的有误，请指正，勿喷哈。希望与正在学习python的朋友共同学习，交流
下面是我的代码实现
# -*- coding: cp936 -*-
#---------------------------------------------
#
#author chile
#version 1.0
#date 2014-01-11
#desc 使用hash实现一个映射容器 ，只有简单的实现
#
#
#---------------------------------------------
class entry:
def __init__(self,key = None,val = None,_next = ''):
self.before = None
self.key = key
self.value = val
self.next = _next
class hashmap():
def __init__(self,length = 16):
self.len = length
self.arr = self.initarr(length)
self.entry = entry()
def hashcode(self,key):
return abs(hash(key)) % self.len
def put(self,key,value):
index = self.hashcode(key)
root = self.arr[index]
self.entry = entry(key = key,val = value)
self.putentry(root, key)
self.arr[index] = root
def putentry(self,entry,key):
if isinstance(entry.next,str):
entry.next = self.entry
else:
self.putentry(entry.next, key)
def get(self,key):
index = self.hashcode(key)
entry = self.arr[index]
if isinstance(entry.next,str):
return None
return self.getentry(entry.next, key)
def remove(self,key):
index = self.hashcode(key)
root = self.arr[index]
if not isinstance(root.next,str):
self.removeentry(root, key)
def initarr(self,len):
arr = []
for v in range(0,len):
arr.append(entry())
return arr
def getentry(self,entry,key):
_key = entry.key
if cmp(key,_key) == 0:
return entry.value
else:
self.getentry(entry.next, key)
def removeentry(self,entry,key):
next = entry.next
if cmp(next.key,key) == 0:
entry.next = next.next
else:
self.removeentry(next,key)
mymap = hashmap()
mymap.put('2', 22)
mymap.put('3', 'vals')
mymap.put('5', 'val5s')
mymap.put('4', 'val4s')
mymap.put('6', 'val6s')
mymap.put('12', 'va12l')
mymap.put('13', 'va13ls')
mymap.put('15', 'val15s')
mymap.put('14', 'val14s')
mymap.put('16', 'val16s')
print mymap.get('3')
print mymap.get('2')
mymap.remove('4')
print mymap.get('14')