List Queue

ListQueue (Queue)

A queue implemented using python's list data structure

__len__(self) special

Get the total number of elements stored in the queue

>>> a_queue = ListQueue()
>>> a_queue.enqueue(1)
>>> len(a_queue)
1

Returns:

Type	Description
int	count of elements in queue

Source code in queues/list_queue.py

def __len__(self) -> int:
    """Get the total number of elements stored in the queue

        >>> a_queue = ListQueue()
        >>> a_queue.enqueue(1)
        >>> len(a_queue)
        1

    :returns: count of elements in queue
    """
    return len(self.__data_store)

dequeue(self)

Remove first element of the queue and return it

>>> a_queue = ListQueue()
>>> a_queue.enqueue(1)
>>> a_queue.dequeue()
1

Returns:

Type	Description
Any	first element of queue

Source code in queues/list_queue.py

def dequeue(self) -> Any:
    """Remove first element of the queue and return it

        >>> a_queue = ListQueue()
        >>> a_queue.enqueue(1)
        >>> a_queue.dequeue()
        1

    :return: first element of queue
    """
    if self.is_empty():
        raise Empty("Queue is empty")
    return self.__data_store.pop(0)

enqueue(self, x)

Insert an element to the end of the queue

>>> a_queue = ListQueue()
>>> a_queue.enqueue(1)

Parameters:

Name	Type	Description	Default
x	Any	element to add to the queue	required

Source code in queues/list_queue.py

def enqueue(self, x: Any) -> None:
    """Insert an element to the end of the queue

        >>> a_queue = ListQueue()
        >>> a_queue.enqueue(1)

    :param x: element to add to the queue
    """
    self.__data_store.append(x)

get_first(self)

Return first element of the queue without removing it

>>> a_queue = ListQueue()
>>> a_queue.enqueue(1)
>>> a_queue.get_first()
1

Returns:

Type	Description
Any	first element of queue

Source code in queues/list_queue.py

def get_first(self) -> Any:
    """Return first element of the queue without removing it

        >>> a_queue = ListQueue()
        >>> a_queue.enqueue(1)
        >>> a_queue.get_first()
        1

    :return: first element of queue
    """
    if self.is_empty():
        raise Empty("Queue is empty")
    return self.__data_store[0]

is_empty(self)

Check if queue contains no elements

>>> a_queue = ListQueue()
>>> a_queue.is_empty()
True
>>> a_queue.enqueue(1)
>>> a_queue.is_empty()
False

Returns:

Type	Description
bool	True if queue is empty, else False

Source code in queues/list_queue.py

def is_empty(self) -> bool:
    """Check if queue contains no elements

        >>> a_queue = ListQueue()
        >>> a_queue.is_empty()
        True
        >>> a_queue.enqueue(1)
        >>> a_queue.is_empty()
        False

    :return: True if queue is empty, else False
    """
    return len(self.__data_store) == 0