MyQueueClass Python

3.5.py

#!/usr/bin/python

# 3.5 implement a MyQueueClass using two stacks.

class MyQueueClass(object):

	def __init__(self):
		self.s1 = []
		self.s2 = []
		self.current_stack = self.s1
		self.isEnqueue = True

	def __switch(self):
		self.isEnqueue = not self.isEnqueue
		from_stack = self.current_stack

		if from_stack == self.s1:
			to_stack = self.s2
		else:
			to_stack = self.s1

		while len(from_stack) > 0:
			n = from_stack.pop()
			to_stack.append(n)

		self.current_stack = to_stack

	def queue(self, n):
		if not self.isEnqueue:
			self.__switch()
		self.current_stack.append(n)

	def dequeue(self):
		if self.isEnqueue:
			self.__switch()
		return self.current_stack.pop()


m = MyQueueClass()

m.queue(1)
m.queue(2)
m.queue(3)
m.queue(4)
m.queue(5)

print m.dequeue()
print m.dequeue()
print m.dequeue()

m.queue(6)

print m.dequeue()
print m.dequeue()
print m.dequeue()



'''


S1
--------v
1 2 3 4 5


S2


'''