mirror of
https://github.com/autistic-symposium/master-algorithms-py.git
synced 2025-04-30 04:36:08 -04:00
88 lines
2.2 KiB
Python
88 lines
2.2 KiB
Python
class Node(object):
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def __init__(self, name, which):
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self.name = name
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self.which = which
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self.next = next
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self.timestamp = 0
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class AnimalShelter(object):
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def __init__(self):
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self.first_cat = None
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self.first_dog = None
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self.last_cat = None
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self.last_dog = None
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self.counter = 0
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def enqueue(self, name, which):
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self.counter += 1
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node = Node(name, which)
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node.timestamp = self.counter
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if which == 'cat':
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if not self.first_cat:
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self.first_cat = node
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if self.last_cat:
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self.last_cat.next = node
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self.last_cat = node
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if which == 'dog':
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if not self.first_dog:
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self.first_dog = node
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if self.last_dog:
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self.last_dog.next = node
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self.last_dog = node
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def dequeueDog(self):
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if self.first_dog:
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node = self.first_dog
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self.first_dog = node.next
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return str(node.name)
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raise Exception('No Dogs!')
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def dequeueCat(self):
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if self.first_cat:
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node = self.first_cat
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self.first_cat = node.next
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return str(node.name)
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raise Exception('No Cats!')
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def dequeueAny(self):
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nodecat = self.first_cat
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nodedog = self.first_dog
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if nodecat and not nodedog:
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return self.dequeueCat()
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elif nodedog and not nodecat:
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return self.dequeueDog()
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elif nodedog and nodecat:
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if nodedog.timestamp < nodecat.timestamp:
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return self.dequeueDog()
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else:
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return self.dequeueCat()
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raise Exception('No Animals!')
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def main():
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qs = AnimalShelter()
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qs.enqueue('bob', 'cat')
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qs.enqueue('mia', 'cat')
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qs.enqueue('yoda', 'dog')
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qs.enqueue('wolf', 'dog')
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assert(qs.dequeueDog() == 'yoda')
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assert(qs.dequeueCat() == 'bob')
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print(qs.dequeueAny() == 'mia')
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if __name__ == '__main__':
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main()
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