This notebook was prepared by Donne Martin. Source and license info is on GitHub.
Refer to the Solution Notebook. If you are stuck and need a hint, the solution notebook's algorithm discussion might be a good place to start.
class Node(object):
def __init__(self, data):
# TODO: Implement me
pass
class Queue(object):
def __init__(self):
# TODO: Implement me
pass
def enqueue(self, data):
# TODO: Implement me
pass
def dequeue(self):
# TODO: Implement me
pass
The following unit test is expected to fail until you solve the challenge.
# %load test_queue_list.py
import unittest
class TestQueue(unittest.TestCase):
# TODO: It would be better if we had unit tests for each
# method in addition to the following end-to-end test
def test_end_to_end(self):
print('Test: Dequeue an empty queue')
queue = Queue()
self.assertEqual(queue.dequeue(), None)
print('Test: Enqueue to an empty queue')
queue.enqueue(1)
print('Test: Dequeue a queue with one element')
self.assertEqual(queue.dequeue(), 1)
print('Test: Enqueue to a non-empty queue')
queue.enqueue(2)
queue.enqueue(3)
queue.enqueue(4)
print('Test: Dequeue a queue with more than one element')
self.assertEqual(queue.dequeue(), 2)
self.assertEqual(queue.dequeue(), 3)
self.assertEqual(queue.dequeue(), 4)
print('Success: test_end_to_end')
def main():
test = TestQueue()
test.test_end_to_end()
if __name__ == '__main__':
main()
Review the Solution Notebook for a discussion on algorithms and code solutions.