20 lines
434 B
Python
20 lines
434 B
Python
from stack import Stack
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class Queue(object):
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def __init__(self):
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self.lhs = Stack()
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self.rhs = Stack()
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def enqueue(self, x):
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self.rhs.push(x)
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def dequeue(self, x):
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y = self.rhs.pop()
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while y:
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self.lhs.push(y)
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y = self.rhs.pop()
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result = self.lhs.pop()
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y = self.lhs.pop()
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while y:
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self.rhs.push(y)
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return result
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