def test_size():
linked_list = DoublyLinkedList()
assert linked_list.size() == 0
linked_list.append(1)
assert linked_list.size() == 1
assert get_multi_node_list().size() == 4
def test_append():
doubly_linked_list = DoublyLinkedList()
doubly_linked_list.append(3)
doubly_linked_list.append(4)
assert doubly_linked_list.size() == 2
assert doubly_linked_list.get(0) == 3
assert doubly_linked_list.get(1) == 4
def get_multi_node_list() -> DoublyLinkedList:
multi_node_list = DoublyLinkedList()
multi_node_list.append(5)
multi_node_list.append(2)
multi_node_list.append(4)
multi_node_list.append(1)
return multi_node_list
class QueueLinkedList(Generic[T]):
"""
Queue backed by a doubly linked list
"""
def __init__(self):
self.linked_list = DoublyLinkedList()
def __len__(self):
return self.linked_list.size()
# O(1)
def dequeue(self) -> T:
return self.linked_list.remove(0)
# O(1)
def enqueue(self, element: T):
self.linked_list.append(element)
def test_init():
linked_list = DoublyLinkedList()
linked_list.append(3)
assert linked_list.size() == 1
assert linked_list.get(0) == 3
def test_append_empty():
doubly_linked_list = DoublyLinkedList()
doubly_linked_list.append(1)
assert doubly_linked_list.size() == 1
assert doubly_linked_list.get(0) == 1