class AnimalShelter(): def __init__(self): self.cat_queue = Queue() self.dog_queue = Queue() self.animals_served = 0 def enqueue(self, incoming_animal): type_of_animal = type(incoming_animal) # https://docs.python.org/3/library/functions.html#type self.animals_served += 1 incoming_animal.animal_id = self.animals_served if type_of_animal == Cat: self.cat_queue.enqueue(incoming_animal) elif type_of_animal == Dog: self.dog_queue.enqueue(incoming_animal) else: raise InvalidOperationError("Sorry, we don't accept that type of animal here.") def dequeue(self, request_type = None): if request_type == "cat": return self.cat_queue.dequeue() elif request_type == "dog": return self.dog_queue.dequeue() elif request_type == None: #which queue is older? next_cat = self.cat_queue.peek().animal_id next_dog = self.dog_queue.peek().animal_id if next_cat < next_dog: return self.cat_queue.dequeue() else: return self.dog_queue.dequeue() else: return None
def test_multiple_dequeue(): q = Queue() q.enqueue('first value') q.enqueue('second value') q.dequeue() q.dequeue() assert q.front == None
def queue_test(): queue = Queue() queue.enqueue(4) queue.enqueue(3) queue.enqueue(2) queue.enqueue(1) return queue
def breadth_first(self, starting_node, action_function=None): list_of_nodes = [] breadth_queue = Queue() breadth_queue.enqueue(starting_node) starting_node.visited = True i = 1 while not breadth_queue.is_empty(): print(f"trip {i} through while loop") i += 1 current_vertex = breadth_queue.dequeue() list_of_nodes.append(current_vertex) current_edges = self._adjacency_list[current_vertex] for edge in current_edges: if edge.vertex.visited == False: breadth_queue.enqueue(edge.vertex) edge.vertex.visited = True # NOTE: Doing this traversal method over the weekend, I choose to give each Vertex an attribute of visited that had a value of True or False. During class on Monday, JB did say that some are set up this way. However, he said he prefers to keep track of the visited nodes by using a variable of type set. This prevents any possibility of leaving an item visited attribute as true. The set variable would be cleared to length 0 at the start of each breadth traversal. for node in self._adjacency_list: node.visted = False list_of_values_of_nodes = list(map(lambda x: x.value, list_of_nodes)) # attempts to get the passed in function to act on the list_of_nodes and thereby append to the list existing in the space from where this method was called is on the next line. # map(action_function(list_of_nodes)) # return list_of_nodes return list_of_values_of_nodes
def test_dequeue(): q = Queue() q.enqueue("apple") q.enqueue("banana") actual = q.dequeue() expected = "apple" assert actual == expected
def test_check_not_empty(): q = Queue() q.enqueue("apple") q.enqueue("banana") actual = q.q_is_empty() expected = False assert actual == expected
def test_enqueue_two(): q = Queue() q.enqueue("apples") q.enqueue("bananas") actual = q.peek() expected = "apples" assert actual == expected
def test_dequeue_when_full(): q = Queue() q.enqueue("apples") q.enqueue("bananas") actual = q.dequeue() expected = "apples" assert actual == expected
def test_peek_queue(): q3 = Queue() q3.enqueue(1) q3.enqueue(3) q3.enqueue(5) q3.enqueue(7) assert q3.peek() == 1 assert not q3.is_empty()
def test_peek_post_dequeue(): q = Queue() q.enqueue("apples") q.enqueue("bananas") q.dequeue() actual = q.peek() expected = "bananas" assert actual == expected
def test_can_successfully_dequeue_out_of_a_queue_the_expected_value(): new_queue = Queue() new_queue.enqueue('Three') new_queue.enqueue('Two') new_queue.enqueue('One') expected = 'Three' actual = new_queue.peek() assert expected == actual
def test_can_successfully_enqueue_multiple_values_into_a_queue(): new_queue = Queue() new_queue.enqueue('Three') new_queue.enqueue('Two') new_queue.enqueue('One') expected = 'Three' actual = new_queue.peek() assert expected == actual
def test_dequeue(): letters = Queue() letters.enqueue('A') letters.enqueue('B') letters.enqueue('C') assert letters.dequeue() == 'A' assert letters.dequeue() == 'B' assert letters.dequeue() == 'C' assert letters.dequeue() is None
def test_dequeue(): q2 = Queue() q2.enqueue(7) q2.enqueue(5) q2.enqueue(3) q2.enqueue(1) assert q2.rear.value == 1 assert q2.dequeue() == 7 assert q2.front.value == 5
def test_queue_peek(): letters = Queue() assert not letters.peek() letters.enqueue('A') assert letters.peek() == 'A' letters.enqueue('B') assert letters.peek() == 'A'
def test_dequeue_multiple(): q4 = Queue() q4.enqueue(7) q4.enqueue(5) q4.enqueue(3) q4.enqueue(1) q4.dequeue() q4.dequeue() q4.dequeue() q4.dequeue() assert q4.front == None assert q4.rear == None assert q4.is_empty()
def queue_vals(): queue = Queue() queue.enqueue(8) queue.enqueue('hi') queue.enqueue(-4) queue.enqueue(6) return queue
def breadth_first_traverse(self, start_vert): """ Returns a list of graph vertex values in breadth-first order :param start_vert: Vertex object :returns: list of vertex values """ q = Queue() output = [] q.enqueue(start_vert) start_vert.visited = True while q.peek(): vert = q.dequeue() output.append(vert.value) for v, w in vert.adjacencies: if not v.visited: q.enqueue(v) v.visited = True self._reset_visited() return output
def traverse(self, node, debug=False): queue = Queue() ret_baby = [] if not node: return 'babies' visited = {} queue.enqueue(node) while queue.peek(): current = queue.dequeue() visited[current] = True if current == 'this queue is empty buddy': break for baby_node in self._adjacency_list[current]: if baby_node == None: break if not baby_node in visited: queue.enqueue(baby_node) ret_baby.append(current.value) if debug: breakpoint() return ret_baby
def queue_3vals(): queue = Queue() queue.enqueue(3) queue.enqueue(-8) queue.enqueue('z') queue.enqueue('a') return queue
def test_peek(): q = Queue() q.enqueue("apple") q.enqueue("banana") q.enqueue("cucumber") actual = q.peek() expected = "apple" assert actual == expected
def test_enqueue_onto_full(): q = Queue() q.enqueue("apple") q.enqueue("banana") q.enqueue("cucumber") actual = q.front.value expected = "apple" assert actual == expected
class AnimalShelter(object): def __init__(self): self._queue = Queue() def enqueue(self, animal): self._queue.enqueue(animal) def dequeue(self, pref): if pref not in ('dog', 'cat'): return None if self._queue.front: curr = self._queue.front prev = None while curr.value.species != pref: prev = curr curr = curr.nxt if prev: prev.nxt = curr.nxt else: self._queue.front = curr.nxt curr.nxt = None return curr.value return None
def breadth_first(self, start): """This method does a breadth first traversal of a graph Arguments: node -- [starting poing of the traversal] Returns: [list] -- [a list of all connected nodes] """ explored = [] queue = Queue() queue.enqueue(start) while queue.peek() is not None: node = queue.dequeue() if node not in explored: explored.append(node) neighbors = self._graph[node] for neighbor in neighbors: queue.enqueue(neighbor[0]) return explored
def traverse_breadth_first(self): q = Queue() q.enqueue(self.root) while q.peek(): curr = q.dequeue() yield curr.value if curr.l_child: q.enqueue(curr.l_child) if curr.r_child: q.enqueue(curr.r_child)
def test_enqueue_multiple(): q1 = Queue() q1.enqueue(1) q1.enqueue(2) q1.enqueue(3) q1.enqueue(4) q1.enqueue(5) assert q1.front.value == 1 assert q1.front.next.value == 2 assert q1.rear.value == 5
def test_dequeue_until_empty(): q = Queue() q.enqueue("apple") q.enqueue("banana") q.enqueue("cucumber") q.dequeue() q.dequeue() q.dequeue() actual = q.q_is_empty() expected = True assert actual == expected
def test_exhausted(): q = Queue() q.enqueue("apple") q.enqueue("banana") q.enqueue("cucumber") q.dequeue() q.dequeue() q.dequeue() actual = q.is_empty() expected = True assert actual == expected
def traverse_breath_first(self): queue = Queue() curr = self.root queue.enqueue(curr) # import pdb; pdb.set_trace() while queue.is_empty(): curr = queue.dequeue() if curr.child_left: queue.enqueue(curr.child_left) if curr.child_right: queue.enqueue(curr.child_right) yield (curr.value)
def breath_first(self): rtn = [] queue = Queue() curr = self.root queue.enqueue(curr) # import pdb; pdb.set_trace() while queue.is_empty(): curr = queue.dequeue() if curr.child_left: queue.enqueue(curr.child_left) if curr.child_right: queue.enqueue(curr.child_right) rtn.append(curr.value) return rtn