chap11 哈希錶鏈接法

from functools import reduce
from operator import add
from random import seed,randint
class Node:
    def __init__(self,key,prev=None,next=None):
        self.key,self.prev,self.next=key,prev,next
class HashTable:
    size=97
    def hfunction(key):
        strs=str(key)
        return reduce(add,map(ord,strs),0)%HashTable.size
    def __init__(self):
        self.T=[Node('dummy') for i in range(self.size)]
        for x in self.T:
            x.prev=x.next=x
    def __getitem__(self,k):
        return self.T[k]
    def __setitem__(self,k,x):
        self.T[k]=x
    def insert(self,x):
        hkey=HashTable.hfunction(x.key)
        x.prev,x.next=self.T[hkey],self.T[hkey].next
        self.T[hkey].next,self.T[hkey].next.prev=x,x
    def search(self,key):
        hkey=self.hfunction(key)
        x=self.T[hkey]
        while x!=None and x.key!=key:
            x=x.next
        return x
    def delete(self,x):
        x.prev.next,x.next.prev=x.next,x.prev
    def print(self):
        for i in range(0,self.size):
            x=self.T[i]
            if x.next==x:
                continue
            print('key=',str(i),':',end='')
            while(True):
                x=x.next
                if x==self.T[i]:
                    break
                print(x.key,end=' ')
            print()
        
h=HashTable()
seed(0)
for i in range(0,100):
    x=randint(0,10000000)
    h.insert(Node(x))
h.print()