Question

Question 1 (20 points): a. Consider the "circular" array implementation of a queue, similar to ArrayQueue that we studied in class, where the only difference is that the initial capacity is set to 4 (INITIAL_CAPACITY=4): class ArrayQueue: INITIAL_CAPACITY = 4 def __init__(self): self.data_arr = make_array(ArrayQueue.INITIAL_CAPACITY) self.num_of_elems = 0 self.front_ind = None def __len__(self): … def is_empty(self): … def enqueue(self, elem): … def dequeue(self): … def first(self): … def resize(self, new_cap): … Show the values of the data members: front_ind, num_of_elems, and the contents of each data_arr[i] after each of the following operations. If you need to increase the capacity of data_arr, add extra slots as described in class.

Answer 1

Answer:

Check the explanation

Explanation:

main. py

class ArrayQueue:

   INITIAL_CAPACITY = 4

   def __init__(self):

       #self. data_arr = make_array(ArrayQueue.INITIAL_CAPACITY)

       self. data_arr = [None] * ArrayQueue.INITIAL_CAPACITY

       self. num_of_elements = 0

       self. front_ind = None

   def __len__(self):

       return self. num_of_elements

   def is_empty(self):

       return self. num_of_elements == 0

   def first(self):

       """ Peak the front of the queue without removing any item. """

       if self. front_ind == None:

           return None

       else:

           return self. data_arr[self.front_ind]

   def enqueue(self, elem):

       """ Add the element to the rear of queue. Extend the queue if necessary. """

       # If queue is empty

       if self. front_ind == None:

           self. front_ind = 0

           self. data_arr[0] = elem

           self. num_of_elements += 1

       else:

           # If the queue is not full

           if self. num_of_elements != len(self. data_arr):

               self. data_arr[(self. front_ind + self. num_of_elements) % len(self. data_arr)] = elem

               self. num_of_elements += 1

           else:

               # Add new cell at the end of data array

               self. data_arr. append(None)

               # Index of new empty cell

               new_cell_index = len(self. data_arr) - 1

               

               # If the last element of queue was the last element of array

               if self. front_ind == 0:

                   self. data_arr[new_cell_index] = elem