class AnimalShelter:
def __init__(self):
self.cats = LinkedList([])
self.dogs = LinkedList([])
self.__stamp = 0
def enqueue(self, animal: Animal):
animal.timestamp = self.__stamp
self.__stamp += 1
if isinstance(animal, Cat):
self.cats.append(animal)
else:
self.dogs.append(animal)
def dequeue_any(self):
if self.cats.head == None:
return self.dequeue_dog()
elif self.dogs.head == None:
return self.dequeue_cat()
dog = self.dogs.head.data
cat = self.cats.head.data
if (dog > cat):
return self.dequeue_dog()
else:
return self.dequeue_cat()
def dequeue_dog(self):
if self.dogs.head == None:
raise Exception()
tmp = self.dogs.head.data
self.dogs.head = self.dogs.head.next
return tmp
def dequeue_cat(self):
if self.cats.head == None:
raise Exception()
tmp = self.cats.head.data
self.cats.head = self.cats.head.next
return tmp
class SimpleAnimalShelter:
CAT = 1
DOG = 2
def __init__(self):
self.list = LinkedList([])
def enqueue(self, animal):
self.list.append(animal)
def dequeue(self):
oldest = self.list.head
if oldest == None:
raise Exception()
self.list.head = self.list.head.next
return oldest
def dequeue_cat(self):
return self.__dequeue_animal(SimpleAnimalShelter.CAT)
def dequeue_dog(self):
return self.__dequeue_animal(SimpleAnimalShelter.DOG)
def __dequeue_animal(self, animal):
if self.list.head == None:
raise Exception()
elif self.list.head.data == animal:
tmp = self.list.head
self.list.head = self.list.head.next
return tmp
oldest = None
n = self.list.head
while n.next != None and n.next.data != animal:
n = n.next
if n.next == None:
raise Exception()
oldest = n.next
n.next = n.next.next
return oldest
def gen_depth_list(root):
if not root:
return []
q: queue.Queue = queue.Queue()
q.put(root)
lst = []
current = LinkedList([root])
while len(current) > 0:
lst.append(current)
parents = current
current = LinkedList([])
for parent in parents:
if parent.left:
current.append(parent.left)
if parent.right:
current.append(parent.right)
return lst