class Stack:
def __init__(self):
self.size = 0
self.storage = LinkedList()
def __len__(self):
return self.storage.get_length()
def push(self, value):
self.storage.add_to_head(value)
def pop(self):
return self.storage.remove_head()
class Queue: # queue class
def __init__(self): # initialize constructor method
self.size = 0 # set size to 0
self.storage = LinkedList() # set storage to LinkedList class
def __len__(self): # method to show length
return self.storage.get_length()
def enqueue(self, value): # method to add a value to the que
self.storage.add_to_tail(value) # append value to items list
self.size += 1 # add to length
def dequeue(self): # method to remove a value from the que
value = self.storage.remove_head() # remove the head value with remove_head method and store it as a value
if value is not None: # if value is not empty
self.size -= 1 # remove 1 from the length
return value
