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https://github.com/donnemartin/interactive-coding-challenges.git
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34 lines
888 B
Python
34 lines
888 B
Python
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class Node(object):
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def __init__(self, data):
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self.data = data
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self.next = None
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class Queue(object):
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def __init__(self):
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self.first = None
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self.last = None
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def enqueue(self, data):
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node = Node(data)
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if self.first is None and self.last is None:
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self.first = node
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self.last = node
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else:
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self.last.next = node
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self.last = node
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def dequeue(self):
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# Empty list
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if self.first is None and self.last is None:
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return None
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# Remove only element from a one element list
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elif self.first == self.last:
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data = self.first.data
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self.first = None
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self.last = None
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return data
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else:
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data = self.first.data
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self.first = self.first.next
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return data |