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Double-ended queue (abbreviated to deque) is a generalized version of the queue data structure that allows insert and delete at both ends. We can implement a Deque class using linked lists. In this question, we define nodes for a deque as: struct Node{ int value; Node* next; Node* prev; }; When a Node object is used for linked lists, we use the next pointer to point to its next node in the list, and use the prev pointer to point to its previous node in the list. If one node does not have a next or previous node (which means it is the last or the first node in this list), its corresponding pointer is set to NULL. We can define a Deque class as follows. class Deque{ public: Deque(); // Initialize an empty Deque. void insertFront(int num); // Add a node at the front of Deque. void insertRear(int num); // Add a node at the rear of Deque. int removeFront(); // Delete a node from front of Deque // and return its value. int removeRear(); // Delete a node from rear of Deque // and return its value. int size() const; // Return the number of nodes. /* More member function declarations are omitted */ private: Node* front; Node* rear; }; For each Deque object, we have two pointers, front and rear. The front pointer is used to point to the first node in the list, and the rear pointer is used to point to the last node. If a deque is empty, both pointer are set to NULL.

Suppose one program contains the following class definition (along with definitions of the member functions, which are omitted here). class Dog{ public: Dog(); Dog(string name_info, string breed_info); Dog(const Dog &input_dog); void bark(); private: string name; string breed; }; Consider the following program statements. Assume they are not in member or friend functions of the Dog class. Analyze each statement and answer the questions below:

When you open a file with access code “w” and begin writing records, the data is immediately written to the file and can be viewed using Notepad or other software tool.

To read first 2 characters from a file, we can use  which of the following notation? 

The ‘closed’ attribute of a file object indicates whether the file is open or not. If the file is closed, ‘closed’ attribute returns True. What would be the outcome of the following code? with open(‘input.txt’, ‘r’) as fp:      fp.read() print(fp.closed)

What would be written to “q5.in” file assume the file already exists and it’s a blank file? Choose the most appropriate answer. f=open(‘q5.in’, ‘r’) f.write(‘test file\n’) f.close()

Opening a file in ‘a’ mode, opens the file for reading

When you issue this file open: fp = open(‘infile.txt’, ‘w’) and then do the following operations: fp.write(‘Line 1’) fp.write(‘Line 2’) fp.write(‘Line 3’) What will the contents of ‘infile.txt’ be when viewing it using Notepad?

Given the following lines of a text file called ‘states.txt’: AlabamaAlaskaArizona What is the display output of the following code? fi = open(‘states.txt’) plines = fi.readlines( ) for p in plines:         print(p[:-1])

The popular image of the bureaucracy is of large, impersonal organizations that are inefficient and unresponsive. Identify one advantage of the federal bureaucracy. Provide a specific example to illustrate. Identify one problem with the federal bureaucracy. Provide a specific example to illustrate.