【DataStructure In Python】Python模拟栈和队列

#! /usr/bin/env python
# DataStructure Stack

class Stack:

    def __init__(self, data=None):
        if data is not None:    
            self.stk = [data]
            self.top = 0
        else:
            self.stk = []
            self.top = -1

    def __str__(self):
        return " ".join([str(x) for x in self.stk])
                    
    def push(self, data):
        self.stk.append(data)
        self.top += 1
    
    def pop(self):
        if self.top == -1:
            print "Stack is empty"
            return 
        return self.stk.pop()
    
    def isEmpty(self):
        if self.top == -1:
            return 1
        else :
            return 0

if __name__ == "__main__":
    stack = Stack()
    for i in range(10):
        stack.push(i)
    print "push:",stack
    print "pop: ",
    for i in range(3):
        print stack.pop(),
    print ""
    print "left:",stack

#! /usr/bin/env python
# DataStructure Queue

class Queue:
    
    def __init__(self, data=None):
        if data is not None:
            self.que = [data]
        else:
            self.que = []

    def __str__(self):
        return " ".join([str(x) for x in self.que])

    def isEmpty(self):
        if len(self.que):
            return 0
        else:
            return 1

    def enQueue(self, data):
        self.que.append(data)

    def deQueue(self):
        return self.que.pop(0)

if __name__ == "__main__":
    queue = Queue()
    for i in range(10, 0, -1):
        queue.enQueue(i)
    print "enQueue:",queue
    print "deQueue:",
    for i in range(3):
        print queue.deQueue(),
    print ""
    print "left:   ",queue