Goal: [10 pts] In our video lecture, we discussed the abstract data type Queue. A queue...

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Goal: [10 pts] In our video lecture, we discussed the abstract data type Queue. A queue is a collection of items where the addition of new items happens at one end (tail) and the removal of existing items occurs at the other end (head) (FIFO). Use the Node class (an object with a data field and a pointer to the next element) to implement the queue data structure with the following operations: • enqueue(item) adds a new Node with value=item to the tail of the queue. It needs the value of the Node and returns nothing. • dequeue () removes the head Node from the queue. It needs no parameters and returns the value of the Node removed from the queue. The queue is modified. • is Empty() tests to see whether the queue is empty. It needs no parameters and returns a boolean value. • • len(queue_object) returns the number of items in the queue. It needs no parameters and returns an integer. reverse() reverses all nodes from the queue. Modifies the original queue and returns nothing. Recursion could be useful here, however, you are allowed to use a helper Python list to assist the process if you want to work iteratively, but you are not allowed to use the reverse method on the Python list. You are not allowed to use any other data structures to copy the elements of the Queue for manipulating purposes in the enqueue and dequeue methods. Tips: You are not allowed to modify the given constructor You can't use queue functions from the Python library, otherwise no credit will be given Starter code contains the special methods_str___ and __repr___, use them to ensure the queue operations are updating the elements in the queue correctly When calling dequeue, you always need to check the size of the queue first to ensure there are elements in the queue. Remember that calling dequeue when the size is 1 should update the head and tail pointers to None class Node: J definit__(self, value): self.value = value self.next = None J def _str_(self): J return "Node({})".format(self.value) class Queue: _repr_ = _str_ >>> x=Queue () >>> x.isEmpty() True >>> x.dequeue () 'Queue is empty' >>> x.enqueue (1) >>> x.enqueue (2) >>> x.enqueue (3) >>> x.dequeue () 1 >>> x.reverse() Head: Node (3) Tail:Node(2) Queue:3 2 def __init__(self): self.head=None self.tail=None self.count=0 def_str_(self): temp=self.head out=[] while temp: out.append(str(temp.value)) temp=temp.next out=' '.join(out) return f'Head:{self.head}Tail:{self.tail}Queue:{out}' _repr__=_ _str_ def isEmpty(self): def def enqueue (self, x): # --- Your code starts here def dequeue (self): # Your code starts here Your code starts here _len_(self): --- Your code starts here def reverse(self): Your code starts here Goal: [10 pts] In our video lecture, we discussed the abstract data type Queue. A queue is a collection of items where the addition of new items happens at one end (tail) and the removal of existing items occurs at the other end (head) (FIFO). Use the Node class (an object with a data field and a pointer to the next element) to implement the queue data structure with the following operations: • enqueue(item) adds a new Node with value=item to the tail of the queue. It needs the value of the Node and returns nothing. • dequeue () removes the head Node from the queue. It needs no parameters and returns the value of the Node removed from the queue. The queue is modified. • is Empty() tests to see whether the queue is empty. It needs no parameters and returns a boolean value. • • len(queue_object) returns the number of items in the queue. It needs no parameters and returns an integer. reverse() reverses all nodes from the queue. Modifies the original queue and returns nothing. Recursion could be useful here, however, you are allowed to use a helper Python list to assist the process if you want to work iteratively, but you are not allowed to use the reverse method on the Python list. You are not allowed to use any other data structures to copy the elements of the Queue for manipulating purposes in the enqueue and dequeue methods. Tips: You are not allowed to modify the given constructor You can't use queue functions from the Python library, otherwise no credit will be given Starter code contains the special methods_str___ and __repr___, use them to ensure the queue operations are updating the elements in the queue correctly When calling dequeue, you always need to check the size of the queue first to ensure there are elements in the queue. Remember that calling dequeue when the size is 1 should update the head and tail pointers to None class Node: J definit__(self, value): self.value = value self.next = None J def _str_(self): J return "Node({})".format(self.value) class Queue: _repr_ = _str_ >>> x=Queue () >>> x.isEmpty() True >>> x.dequeue () 'Queue is empty' >>> x.enqueue (1) >>> x.enqueue (2) >>> x.enqueue (3) >>> x.dequeue () 1 >>> x.reverse() Head: Node (3) Tail:Node(2) Queue:3 2 def __init__(self): self.head=None self.tail=None self.count=0 def_str_(self): temp=self.head out=[] while temp: out.append(str(temp.value)) temp=temp.next out=' '.join(out) return f'Head:{self.head}Tail:{self.tail}Queue:{out}' _repr__=_ _str_ def isEmpty(self): def def enqueue (self, x): # --- Your code starts here def dequeue (self): # Your code starts here Your code starts here _len_(self): --- Your code starts here def reverse(self): Your code starts here

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