Deck 17: Stacks and Queue

Question 1

What is the output of the following code?

A) x = 4
B) x = 5
C) x = 6
D) x = 9

Answer 1

D

Question 2

The infix expression
(a + b) * (c - d / e) + f
is equivalent to the postfix expression
ab + cde /-* f +

Answer 2

True

Question 3

A queue is a First In First Out data structure.

Answer 3

True

Question 4

Postfix notation requires the use of parentheses to enforce operator precedence.

Question 5

The expression a + b is the same in both infix notation and postfix notation.

Question 6

You can perform the operation ____ to remove the top element from the stack.

A) dequeue
B) top
C) pop
D) push

Question 7

If you try to add a new item to a full stack, the resulting condition is called an outflow.

Question 8

Popping an element from an empty stack is called ____.

A) overflow
B) underflow
C) exception
D) overloading

Question 9

The ____ element of the stack is the last element added to the stack.

A) top
B) bottom
C) head
D) tail

Question 10

The default constructor for the linked implementation of a stack initializes the stack to an empty state when a stack object is declared.

Question 11

You can perform the add operation, called ____, to add an element onto the stack.

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

Question 12

If you try to add a new item to a full stack, the resulting condition is called a(n) ____.

A) override
B) overflow
C) overload
D) underflow

Question 13

When a stack is implemented as an array, the array is empty if the value of stackTop is ____.

A) zero
B) one
C) nonzero
D) equal to the size of the array

Question 14

In the linked implementation of stacks, the memory to store the stack elements is allocated statically.

Question 15

In the array representation of a stack, if a value called stackTop indicates the number of elements in the stack, then stackTop-1 points to the top item of the stack.

Question 16

The bottom element of the stack is the last element added to the stack.

Question 17

A(n) ____ is a list of homogenous elements in which the addition and deletion of elements occurs only at one end.

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

Question 18

A stack is a(n) ____ data structure.

A) FIFO
B) FILO
C) LIFO
D) LILO

Question 19

A stack can be implemented as either a(n) ____ or a linked structure.

A) map
B) struct
C) queue
D) array

Question 20

The addition and deletion of elements of a stack occurs only at the ____ of the stack.

A) head
B) bottom
C) top
D) middle

Question 21

A technique in which one system models the behavior of another system is called ____.

A) imitation
B) recursion
C) simulation
D) stimulation

Question 22

The postfix expression 2 4 6 * + 15 - 21 7 / + = evaluates to ____.

A) 4
B) 14
C) 24
D) 26

Question 23

In ____________________ notation, operators are written after the operands.

Question 24

What is the output of the following code?

A) x = 2
Y = 4
B) x = 4
Y = 3
C) x = 2
Y = 3
D) x = 3
Y = 2

Question 25

The following expression (a - b) * (c + d) is equivalent to which of the following postfix expressions?

A) a b c d - + *
B) a b - c d + *
C) a b - + c d *
D) - + * a b c d

Question 26

What is the output of the following code?

A) x = 5
Y = 6
B) x = 4
Y = 3
C) x = 5
Y = 3
D) x = 11
Y = 6

Question 27

The ____________________ constructor is called when a stack object is passed as a (value) parameter to a function.

Question 28

____________________ techniques are used when it is too expensive or dangerous to experiment with real systems.

Question 29

What is the output of the following code? ​
​

A) 6 2 3 3
B) 6 2 4 2
C) 6 3 3 3
D) 6 4 2 3

Question 30

The elements at the ____________________ of the stack have been in the stack the longest.

Question 31

A queue is a data structure in which the elements are ____.

A) added to the rear and deleted from the front
B) added to and deleted from the rear
C) added to and deleted from the front
D) added and deleted in the middle

Question 32

In evaluating a postfix expression, when an equal sign (=) is encountered, how many elements must the stack contain so that no error is generated?

A) none
B) one
C) two
D) three

Question 33

In the array representation of a stack, the stack is initialized simply by setting stackTop to ____________________.

Question 34

The postfix expression 5 6 + 4 * 10 5 / - = evaluates to ____.

A) 10
B) 30
C) 42
D) 44

Question 35

To describe a queuing system, we use the term ____ for the object receiving the service.

A) receiver
B) server
C) customer
D) provider

Question 36

An array is a(n) ____________________ access data structure.

Question 37

The postfix expression 3 5 + 2 ; 6 - = will generate an error, because it ____.

A) contains an illegal operator
B) does not have enough operands
C) has too many operands
D) has too many operators

Question 38

Which of the following is listed in the chapter as a basic operation performed on a queue?

A) push
B) pop
C) isEmptyQueue
D) top

Question 39

The postfix expression 14 2 5 + = will generate an error, because ____.

A) it contains an illegal operator
B) it does not have enough operands
C) it has too many operators
D) there will be too many elements in the stack when the equal sign is encountered

Question 40

To describe a queuing system, we use the term ____ for the object that provides the service.

A) client
B) server
C) customer
D) provider

Question 41

In a(n) ____________________ simulation, the clock is implemented as a counter, and the passage of, say, one minute can be implemented by incrementing the counter by 1.

Question 42

In a queuing system, every customer has a customer number, arrival time, ____________________ time, transaction time, and departure time.

Question 43

When describing a queuing system, we use the term ____________________ to refer to the time it takes to serve a customer.