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58 lines
1.4 KiB
Python
58 lines
1.4 KiB
Python
"""Queue represented by a pseudo stack (represented by a list with pop and append)"""
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class Queue:
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def __init__(self):
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self.stack = []
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self.length = 0
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def __str__(self):
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printed = "<" + str(self.stack)[1:-1] + ">"
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return printed
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"""Enqueues {@code item}
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@param item
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item to enqueue"""
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def put(self, item):
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self.stack.append(item)
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self.length = self.length + 1
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"""Dequeues {@code item}
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@requirement: |self.length| > 0
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@return dequeued
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item that was dequeued"""
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def get(self):
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self.rotate(1)
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dequeued = self.stack[self.length - 1]
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self.stack = self.stack[:-1]
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self.rotate(self.length - 1)
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self.length = self.length - 1
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return dequeued
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"""Rotates the queue {@code rotation} times
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@param rotation
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number of times to rotate queue"""
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def rotate(self, rotation):
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for i in range(rotation):
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temp = self.stack[0]
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self.stack = self.stack[1:]
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self.put(temp)
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self.length = self.length - 1
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"""Reports item at the front of self
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@return item at front of self.stack"""
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def front(self):
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front = self.get()
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self.put(front)
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self.rotate(self.length - 1)
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return front
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"""Returns the length of this.stack"""
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def size(self):
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return self.length
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