Python实现Map数据结构

class HashTable:
	def __init__(self):
		# 初始化两个list，一个用来保存键值，一个用来保存值
		self.size = 11
		self.slots = [None] * self.size
		self.data = [None] * self.size
	# 定义Hash函数，使用余数法
	def hashFunction(self, key, size):
		return (key % size)
	# 定义线性探测hash函数
	def rehash(self, oldhash, size):
		return (oldhash + 1) % size
	# 插入键值对
	def put(self, key, data):
		#　得到Ｈａｓｈ值
		hashvalue = self.hashFunction(key, len(self.slots))
		# 查找当前hash值对应位置的键值是否为空，为空则插入
		if self.slots[hashvalue] == None:
			self.slots[hashvalue] = key
			self.data[hashvalue] = data
		# 不为空则更新
		else:
			if self.slots[hashvalue] == key:
				self.data[hashvalue] = data
			else:
				# 否则继续查找下一个位置，这里使用线性探测器去解决Hash冲突问题
				nextslot = self.rehash(hashvalue, len(self.slots))
				while self.slots[nextslot] != None and self.slots[nextslot] != key:
					nextslot = self.rehash(nextslot, len(self.slots))

			if self.slots[nextslot] == None:
				self.slots[nextslot] = key
				self.data[nextslot] = data
			else:
				self.data[nextslot] = data
	# 重载Python的magic函数
	def __getitem__(self, key):
		return self.get(key)
	# 重载Python的magic函数
	def __setitem__(self, key, data):
		self.put(key, data)
	# 拿键值方法和存放方法一样
	def get(self, key):
		startslot = self.hashFunction(key, len(self.slots))

		data = None
		flag = False
		stop = False
		pos = startslot

		while self.slots[startslot] != None and not flag and not stop:
			if self.slots[pos] == key:
				flag = True
				data = self.data[pos]
			else:
				pos = self.rehash(pos, len(self.slots))
				if pos == startslot:
					stop = True
		return data


if __name__ == '__main__':
	H = HashTable()
	H[54] = 'cat'
	H[26] = 'dog'
	H[93] = 'lion'
	H[17] = 'tiger'
	H[77] = 'bird'
	H[31] = 'cow'
	H[44] = 'goat'
	H[55] = 'pig'
	H[20] = 'chicken'
	H[8] = 'mouse'

	print(H.slots)
	print(H.data)