I need assistence on this problem that I can seem to figure it out. Any help is highly appracticed.



The question says:



The file Queue_array.py contains the array implementation of the Queue ADT.



We have to add the contents of this file to our login_data_structures project in Eclipse.



For the Queue_array library we have to complete the implementation of the insert method.
For the Queue_array library we have to complete the implementation of the remove and peek methods.


The Queue_arrary.py:

from copy import deepcopy


class Queue:

    def __init__(self):
        """
        -------------------------------------------------------
        Initializes an empty queue. Data is stored in a Python list.
        Use: queue = Queue()
        -------------------------------------------------------
        Returns:
            a new Queue object (Queue)
        -------------------------------------------------------
        """
        self._values = []

    def is_empty(self):
        """
        -------------------------------------------------------
        Determines if the queue is empty.
        Use: b = queue.is_empty()
        -------------------------------------------------------
        Returns:
            True if queue is empty, False otherwise.
        -------------------------------------------------------
        """
        return len(self._values) == 0

    def is_full(self):
        """
        -------------------------------------------------------
        Determines if the queue is full. (Given the expandable nature
        of the Python list _values, the queue is never full.)
        Use: b = queue.is_full()
        -------------------------------------------------------
        Returns:
            True if queue is full, False otherwise.
        -------------------------------------------------------
        """
        return False

    def __len__(self):
        """
        -------------------------------------------------------
        Returns the length of the queue.
        Use: n = len(queue)
        -------------------------------------------------------
        Returns:
            the number of values in queue.
        -------------------------------------------------------
        """
        return len(self._values)

    def insert(self, value):
        """
        -------------------------------------------------------
        Adds a copy of value to the rear of the queue.
        Use: queue.insert(value)
        -------------------------------------------------------
        Parameters:
            value - a data element (?)
        Returns:
            None
        -------------------------------------------------------
        """

        # your code here

        return

    def remove(self):
        """
        -------------------------------------------------------
        Removes and returns value from the queue.
        Use: value = queue.remove()
        -------------------------------------------------------
        Returns:
            value - the value at the front of the queue - the value is
            removed from queue (?)
        -------------------------------------------------------
        """
        assert len(self._values) > 0, "Cannot remove from an empty queue"

        # your code here

        return value

    def peek(self):
        """
        -------------------------------------------------------
        Peeks at the front of queue.
        Use: value = queue.peek()
        -------------------------------------------------------
        Returns:
            value - a copy of the value at the front of queue -
            the value is not removed from queue (?)
        -------------------------------------------------------
        """
        assert len(self._values) > 0, "Cannot peek at an empty queue"

        # your code here

        return value

    def __iter__(self):
        """
        FOR TESTING ONLY
        -------------------------------------------------------
        Generates a Python iterator. Iterates through the queue
        from front to rear.
        Use: for value in queue:
        -------------------------------------------------------
        Returns:
            value - the next value in the queue (?)
        -------------------------------------------------------
        """
        for value in self._values:
            yield value


The things we are being tested on:



Test 'is_empty' with various values: '[]'
Test 'is_empty' with various values: '[99]'
Test 'insert' with various values: '[99]'
Test 'insert' with various values: '[33, 11, 22, 55, 44]'
Test 'remove' with various values: '[99]'
Test 'remove' with various values: '[11, 22, 33, 44]'
Test 'remove' with various values: '[33, 11, 22, 55, 44]'
Test 'peek' with various values: '[99]'
Test 'peek' with various values: '[33, 11, 22, 55, 44]'
Test for assertion fails: 'peek'
Test for assertion fails: 'remove'
Test various methods for proper use of 'deepcopy': 'insert'
Test various methods for proper use of 'deepcopy': 'peek'
Test class for calls to forbidden Python functions: 'remove'
Test class for calls to forbidden Python functions: 'input'
Test class for calls to forbidden Python functions: 'print'
Test all methods for multiple calls to 'return':


We are given a hint that is suppose to be helpful:



Although the Stack ADT is a LIFO (Last In, First Out) data structure, and the Queue ADT is a FIFO data structure, they share many similarities in their implementations. Use the Stack ADT implementations as a guideline for implementing your queues.