List Stack

ListStack (Stack)

A stack implemented using python's list data structure

__len__(self) special

Get the total number of elements stored in the stack

>>> a_stack = ListStack()
>>> a_stack.push(1)
>>> len(a_stack)
1

Returns:

Type	Description
int	count of elements in stack

Source code in stacks/list_stack.py

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

        >>> a_stack = ListStack()
        >>> a_stack.push(1)
        >>> len(a_stack)
        1

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

is_empty(self)

Check if stack contains no elements

>>> a_stack = ListStack()
>>> a_stack.is_empty()
True
>>> a_stack.push(1)
>>> a_stack.is_empty()
False

Returns:

Type	Description
bool	True if stack is empty, else False

Source code in stacks/list_stack.py

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

        >>> a_stack = ListStack()
        >>> a_stack.is_empty()
        True
        >>> a_stack.push(1)
        >>> a_stack.is_empty()
        False

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

peek(self)

Get element at the top of the stack without removing it

>>> a_stack = ListStack()
>>> a_stack.push(1)
>>> a_stack.peek()
1

Returns:

Type	Description
Any	element at top of stack

Source code in stacks/list_stack.py

def peek(self) -> Any:
    """Get element at the top of the stack without removing it

        >>> a_stack = ListStack()
        >>> a_stack.push(1)
        >>> a_stack.peek()
        1

    :return: element at top of stack
    """
    if self.is_empty():
        raise Empty("Stack is empty")
    return self.__data_store[-1]

pop(self)

Get element at the top of the stack, and remove it from the stack

>>> a_stack = ListStack()
>>> a_stack.push(1)
>>> a_stack.pop()
1

Returns:

Type	Description
Any	element at top of stack

Source code in stacks/list_stack.py

def pop(self) -> Any:
    """Get element at the top of the stack, and remove it from the stack

        >>> a_stack = ListStack()
        >>> a_stack.push(1)
        >>> a_stack.pop()
        1

    :return: element at top of stack
    """
    if self.is_empty():
        raise Empty("Stack is empty")
    return self.__data_store.pop()

push(self, x)

Insert element x to the top of the stack

>>> a_stack = ListStack()
>>> a_stack.push(1)

Parameters:

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

Source code in stacks/list_stack.py

def push(self, x: Any):
    """Insert element x to the top of the stack

        >>> a_stack = ListStack()
        >>> a_stack.push(1)

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