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python實現堆疊和佇列

1.python實現堆疊,可先將Stack類寫入檔案stack.py,在其它程式檔案中使用from stack import Stack,然後就可以使用堆疊了。stack.py的程式如下:

class Stack():
	def __init__(self,size):
		self.size=size;
		self.stack=[];
		self.top=-1;
	def push(self,ele):        #入棧之前檢查棧是否已滿
		if self.isfull():
			raise exception("out of range");
		else:
			self.stack.append(ele);
			self.top=self.top+1;
	def pop(self):             # 出棧之前檢查棧是否為空
		if self.isempty():
			raise exception("stack is empty");
		else:
			self.top=self.top-1;
			return self.stack.pop();
	
	def isfull(self):
		return self.top+1==self.size;
	def isempty(self):
		return self.top==-1;
		


再寫一個程式檔案,stacktest.py,使用棧,內容如下:

#!/usr/bin/python 
from stack import Stack
s=Stack(20);
for i in range(3):
	s.push(i);
s.pop()
print s.isempty();

2.python 實現佇列:

class Queue():
	def __init__(self,size):
		self.size=size;
		self.front=-1;
		self.rear=-1;
		self.queue=[];
	def enqueue(self,ele):  #入隊操作
		if self.isfull():
			raise exception("queue is full");
		else:
			self.queue.append(ele);
			self.rear=self.rear+1;
	def dequeue(self):      #出隊操作
		if self.isempty():
			raise exception("queue is empty");
		else:
			self.front=self.front+1;
			return self.queue[self.front];
	def isfull(self):
		return self.rear-self.front+1==self.size;
	def isempty(self):
		return self.front==self.rear;
	
q=Queue(10);
for i in range(3):
	q.enqueue(i);
print q.dequeue();
print q.isempty();