Deck 8: Queues

Question 1

Which of the following code fragments is used to delete the item at the front of a queue represented by a circular array?

A)front = MAX_QUEUE - front;
--count;
B)front = front - back;
--count;
C)front = (front+1)% MAX_QUEUE;
--count;
D)front = (back+1)% MAX_QUEUE;
--count;

Answer 1

C

Question 2

To initialize a queue that is represented by a circular array,front is set to ______.

A)0
B)1
C)MAX_QUEUE
D)MAX_QUEUE - 1

Answer 2

A

Question 3

In a queue,items can be added ______.

A)only at the front of the queue
B)only at the back of the queue
C)either at the front or at the back of the queue
D)at any position in the queue

Answer 3

B

Question 4

Which of the following is the code to insert a new node,referenced by newNode,into an empty queue represented by a circular linked list?

A)newNode.setNext(lastNode);
B)lastNode.setNext(lastNode);
LastNode = newNode;
C)newNode.setNext(lastNode);
NewNode = lastNode;
D)newNode.setNext(newNode);
LastNode = newNode;

Question 5

Which of the following methods of QueueInterface does NOT throw a QueueException?

A)enqueue
B)dequeue
C)dequeueAll
D)peek

Question 6

The Java ______ operator is used to obtain the wraparound effect of a circular array-based queue.

A)*
B)+
C)%
D)/

Question 7

Which of the following ADTs is like a line of people?

A)list
B)stack
C)queue
D)tree

Question 8

A reference-based implementation of a queue that uses a circular linked list would need at least ______ external references.

A)one
B)two
C)three
D)four

Question 9

The ______ operation retrieves and removes the front of a queue.

A)isEmpty
B)enqueue
C)dequeue
D)peek

Question 10

Which of the following is NOT an ADT queue operation?

A)enqueue
B)isEmpty
C)pop
D)peek

Question 11

A reference-based implementation of a queue that uses a linear linked list would need at least ______ external references.

A)one
B)two
C)three
D)four

Question 12

Which of the following operations leaves a queue unchanged?

A)enqueue
B)dequeue
C)dequeueAll
D)peek

Question 13

The ______ operation retrieves the item that was added earliest to a queue,but does not remove that item.

A)enqueue
B)dequeue
C)dequeueAll
D)peek

Question 14

The ______ operation adds a new item to a queue.

A)enqueue
B)dequeue
C)push
D)peek

Question 15

To initialize a queue that is represented by a circular array,back is set to ______.

A)0
B)1
C)MAX_QUEUE
D)MAX_QUEUE - 1

Question 16

The ADT ______ allows you to insert into,delete from,and inspect the item at any position of the ADT.

A)stack
B)queue
C)list
D)array

Question 17

If a queue is implemented as the ADT list,which of the following queue operations can be implemented as list.remove(1)?

A)enqueue()
B)dequeue()
C)isEmpty()
D)peek()

Question 18

In an implementation of a queue uses the ADT list,which of the following can be used to implement the operation enqueue(newItem)?

A)list.add(list.size(),newItem)
B)list.add(list.size()+1,newItem)
C)list.add(newItem.size(),newItem)
D)list.add(newItem.size()+1,newItem)

Question 19

Operations on a queue can be carried out at ______.

A)its front only
B)its back only
C)both its front and back
D)any position in the queue

Question 20

If a queue is implemented as the ADT list,which of the following queue operations can be implemented as list.get(1)?

A)enqueue()
B)dequeue()
C)isEmpty()
D)peek()

Question 21

Which of the following is an operation of the ADT list?

A)pop
B)dequeue
C)peek
D)remove

Question 22

The line of customers in a bank can be represented as a(n)______.

A)list
B)queue
C)stack
D)array

Question 23

Which of the following is true about a time-driven simulation of a bank?

A)arrival times are obtained from an input file
B)transaction times are obtained from an input file
C)currentTime is incremented by 1 to simulate the ticking of a clock
D)no action is required between events

Question 24

In an event-driven simulation of a bank,the arrival of a customer is an internal event.

Question 25

In the ADT list,items can be added ______.

A)only at the front of the list
B)only at the back of the list
C)either at the front or at the back of the list
D)at any position in the list

Question 26

Operations of the ADT stack can be viewed as general versions of the list and queue operations.

Question 27

In an event-driven simulation of a bank,which of the following is an internal event?

A)the arrival at the bank of a new customer
B)the start of the transaction of a customer
C)the end of the transaction of a customer
D)the departure from the bank of a customer

Question 28

New items enter a queue at its front.

Question 29

Which of the following is an operation of the ADT stack?

A)enqueue
B)push
C)add
D)get

Question 30

In an event-driven simulation of a bank,the departure times of customers are determined by the simulation.

Question 31

The enqueue operation of the ADT queue is similar to the ______ operation of the ADT stack.

A)isEmpty
B)peek
C)push
D)pop

Question 32

If a string is added to a stack,characters removed from the stack will occur in the order in which they appear in the original string.

Question 33

The pop operation of the ADT stack is similar to the ______ operation of the ADT queue.

A)isEmpty
B)enqueue
C)dequeue
D)peek

Question 34

A queue can be used to preserve the order of occurrences.

Question 35

In a time-driven simulation,no action is required between events.

Question 36

In an event-driven simulation of a bank,which of the following equations can be used to determine the time of a customer's departure?

A)time of next departure = current time - arrival time
B)time of next departure = time service begins + length of transaction
C)time of next departure = arrival time + length of transaction
D)time of next departure = current time - (arrival time + time service begins)

Question 37

The addition of an item to an empty queue is a special case.

Question 38

The first item to be added to a queue is the first item to be removed from the queue.

Question 39

An event list for an event-driven simulation of a bank contains ______.

A)all arrival events
B)all arrival events that will occur but have not occurred yet
C)all departure events
D)all departure events that will occur but have not occurred yet
E)all arrival and departure events that will occur but have not occurred yet

Question 40

Rightward drift is a problem that is encountered in a reference-based implementation of a queue.

Question 41

What is meant by the first-in,first-out property of a queue?

Question 42

What is a deque?

Question 43

What is the action performed by the dequeue operation?

Question 44

What is the action performed by the enqueue operation?

Question 45

What is the goal of a simulation?

Question 46

What is the difference between an external event and an internal event?

Question 47

Write the code fragment to insert a new node,referenced by newNode,into a nonempty queue represented by a circular linked list.

Question 48

Write the code fragment to insert the item newItem into a queue that is represented by a circular array.

Question 49

What is the action performed by the dequeueAll operation?

Question 50

What is the advantage an implementation of a queue that uses the ADT list over an implementation that uses a linked list?

Question 51

What are three examples of position-oriented ADT?

Question 52

Write the code fragment to remove the front item of a queue that contains more than one items and which is represented by a circular linked list.

Question 53

If an object is inserted into a queue,how soon can it be removed?

Question 54

Give an example of a queue that one may find in a computer system.

Question 55

Define the problem of rightward drift in an array-based implementation of a queue.

Question 56

Give two examples of run-time errors or exceptions that may occur when we enqueue or dequeue.

Question 57

What is the action performed by the peek operation?

Question 58

What is an event-driven simulation?

Question 59

What is the main difference between a stack and a queue?

Question 60

If you wanted to write a program to simulate queues in front a bank teller,on what basis would you decide on a maximum size of your queue?