Deck 6: The Repetition Structure

Question 1

Programmers use a(n) ____ when they need the computer to repeatedly process one or more program instructions until some condition is met, at which time the ____ ends.

A) list box
B) loop
C) index
D) counter

Answer 1

B

Question 2

The assignment statement that updates a counter or an accumulator is placed within the loop in a procedure.

Answer 2

True

Question 3

The symbol used to represent a loop condition on a flowchart is the ____ symbol.

A) diamond
B) rectangle
C) hexagon
D) parallelogram

Answer 3

A

Question 4

The repetition programming structure is used to make decisions in a program.

Question 5

A(n) ____ is a numeric variable used for adding together something.

A) counter
B) updater
C) incrementer
D) accumulator

Question 6

In either pretest or posttest loops, the controlling condition is evaluated with each repetition.

Question 7

Which of the following loop structures always executes at least once?

A) pretest
B) posttest
C) top-driven
D) selection

Question 8

The loop created by the For...Next statement is a ____ loop.

A) posttest
B) pretest
C) selection
D) sequential

Question 9

A counter is always incremented by a constant value.

Question 10

Which of the following statements adds the number stored in the decPrice variable to the number stored in the decSubtotal variable, and then assigns the result to the decSubtotal variable?

A) decSubtotal =+ decPrice
B) decPrice =+ decSubtotal
C) decSubtotal += decPrice
D) decPrice += decSubtotal

Question 11

To leave a Do...Loop structure earlier than its full completion, you must execute a(n) ____ statement.

A) End Do
B) Bypass
C) Leave
D) Exit Do

Question 12

In a Do...Loop statement, the keyword While indicates that the loop instructions should be processed while the condition is false.

Question 13

Like the condition in a selection structure, the condition in a loop must evaluate to either True or False.

Question 14

If the stepValue is omitted when coding a For...Next statement, the stepValue is ____ at execution time.

A) -1
B) 0
C) 0.1
D) 1

Question 15

The startValue in a For...Next loop structure may be omitted.

Question 16

____ means assigning a beginning value to a counter or an accumulator.

A) Introducing
B) Initializing
C) Incrementing
D) Updating

Question 17

In a pretest loop, the evaluation of the condition occurs after the instructions within the loop are processed.

Question 18

You can make a list box any size you want.

Question 19

A ____ structure is also referred to as a loop.

A) selection
B) sequence
C) repetition
D) recursion

Question 20

In a Do...Loop statement, a condition can be phrased as either a looping condition or a loop enter condition.

Question 21

You can delay program execution using the ____ method.

A) Delay
B) Rest
C) Sleep
D) Break

Question 22

You can use either the SelectedItem or ____ property to determine whether an item is selected in a list box.

A) Selection
B) SelectedIndex
C) ItemChoice
D) Items

Question 23

You can stop an endless loop by clicking Debug on the menu bar, and then clicking ____.

A) Stop Debugging
B) Cancel Debugging
C) Abort Debugging
D) End Debugging

Question 24

Which of the following statements pauses program execution for 3 seconds?

A) System.Threading.Thread.Pause(300)
B) System.Threading.Thread.Sleep(300)
C) System.Threading.Thread.Pause(3000)
D) System.Threading.Thread.Sleep(3000)

Question 25

You should use a ____ control to provide keyboard access to a list box.

A) radio button
B) text
C) check box
D) label

Question 26

A(n) ____ read is used to prepare or set up a loop.

A) priming
B) initialization
C) preparation
D) set up

Question 27

Visual Basic's ____ class contains many methods that your applications can use to perform financial calculations.

A) Money
B) Monetary
C) Finance
D) Financial

Question 28

Adding increments of a negative number is referred to as ____.

A) decrementing
B) initializing
C) deprocessing
D) negating

Question 29

The number of choices the user can select from a list box is controlled by the list box's ____ property.

A) Selection
B) Display
C) Control
D) SelectionMode

Question 30

In a nested repetition structure, one loop, referred to as the ____ loop, is placed entirely within another loop, called the ____ loop.

A) inner, outer
B) primary, secondary
C) minor, major
D) dependent, independent

Question 31

Case-Based Critical Thinking Questions Case 1 - XYZ Solutions
You have just started working for XYZ Solutions as a programmer. Your first assignment is to review and correct various code so that you can become familiar with the company's programs.
The following code is not working properly. The message should display four times. What needs to be changed for the code to work properly?
Do While intCounter
MessageBox.Show("OK")
IntCounter = intCounter + 1
Loop

A) intCounter should be changed to intCounter = 5
B) intCounter should be changed to intCounter > 5
C) intCounter = 1 should be added before the Do statement
D) intCounter = 0 should be added before the Do statement

Question 32

The ____ method ensures that any code appearing before it that affects the interface's appearance is processed.

A) Process
B) Affect
C) Apply
D) Refresh

Question 33

You use the ____ tool in the toolbox to add a list box to an interface.

A) LBox
B) ListBox
C) List
D) Box

Question 34

Each time either the user or a statement selects an item in a list box, the list box's SelectedValueChanged and ____ events occur.

A) SelectedItemChanged
B) SelectionChanged
C) SelectedIndexChanged
D) ItemChanged

Question 35

Case-Based Critical Thinking Questions Case 1 - XYZ Solutions
You have just started working for XYZ Solutions as a programmer. Your first assignment is to review and correct various code so that you can become familiar with the company's programs.
How many times will the message display based on the counter being initialized to 0?
IntCounter = 0
Do While intCounter
MessageBox.Show("OK")
IntCounter = intCounter + 1
Loop

A) zero
B) one
C) four
D) five

Question 36

You can use a ____ to display a list of choices from which the user can select zero choices, one choice, or more than one choice.

A) list box
B) radio button group
C) check box
D) list

Question 37

In a For...Next statement, if stepValue is positive, then startValue must be ____ endValue for the loop instructions to be processed.

A) less than
B) more than
C) less than or equal to
D) more than or equal to

Question 38

A list box should contain a minimum of ____ item(s).

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

Question 39

Which of the following statements selects the "blue" item, which appears fourth in the lstColor control?

A) lstColor.SelectedIndex = 3
B) lstColor.SelectedIndex = 4
C) lstColor.SelectedItem = 3
D) lstColor.SelectedItem = 4

Question 40

A unique number called a(n) ____ identifies each item in a collection.

A) counter
B) index
C) accumulator
D) tracker

Question 41

Explain the purpose of priming and update reads in a program.

Question 42

What is a list box? Provide two of the Windows standards for its use on a form.

Question 43

What is an accumulator? What does it mean to initialize and update an accumulator in a program?

Question 44

Explain the difference between a pretest loop and a posttest loop.

Question 45

Case-Based Critical Thinking Questions Case 1 - XYZ Solutions
You have just started working for XYZ Solutions as a programmer. Your first assignment is to review and correct various code so that you can become familiar with the company's programs.
You changed the Do clause to the correct For clause in the previous problem. You also changed the Loop keyword to the Next keyword for the For...Next loop. What else needs to be changed about the Do loop?

A) The statement before the loop declaring the counter variable needs to be removed.
B) The statement within the loop incrementing the counter variable needs to be removed.
C) You need to add a step value to the For clause because the default step value is 0.
D) a and b

Question 46

Write a pretest loop that adds together the integers 2, 4, 6, 8, 10, 12, 14, 16, 18, and 20. Use the intNum variable to keep track of the integers. Store the result in the intResult variable (which contains the number 0). Use the For...Next statement.

Question 47

Write a counter-controlled loop that adds 5, 10, 15, 20, 25, and 30 to the lstMinutes control.

Question 48

Case-Based Critical Thinking Questions Case 1 - XYZ Solutions
You have just started working for XYZ Solutions as a programmer. Your first assignment is to review and correct various code so that you can become familiar with the company's programs.
Your supervisor wants you to change the Do...Loop in the previous problem to a For...Next loop. He also wants the message to display only three times. Which of the following For clauses should you use?

A) For intCounter As Integer = 1 To 4
B) For intCounter As Integer = 1 To 3
C) For intCounter As Integer = 0 To 3
D) For intCounter = 1 To 3

Question 49

'fill list boxes with values for men's pant sizes for
'pant waist and pant length
For intWaist As Double = 28 to 46
lstWaist.Items(intWaist.ToString("N0"))
Next intWaist
SelectedItem = "28"
For intLength As Integer = 26 to 36 Step .5
lstLength.Items.Add(dblLength.ToString("N1"))
Next dblLength
lstLength.SelectedIndex = "26"

Question 50

Write a pretest loop that adds together integers from 1 to 50. Use the intNumber variable (which contains the number 1) to keep track of the integers. Store the result in the intResult variable (which contains the number 0). Use the Do...Loop statement and the While keyword.

Question 51

The strCode variable contains an uppercase letter. Write two different Do...Loop clauses that process the loop instructions as long as the value in the strCode variable is either A or B. Use the Until keyword in the first clause, and use the While keyword in the second clause.

Question 52

Problems - Correcting Logic and Code Errors
The following sample of code contains errors. Rewrite the incorrect statements to correct all errors.
An application allows the user to enter a salary amount. The application should then calculate and display the possible bonuses based on that salary, using bonus rates of 3-6% in increments of .5%.
' displays bonus amounts using rates
' of 3% - 6% in increments of .5%
Dim dblSalary As Decimal
Dim decBonus As Decimal
TryParse(txtSalary.Text, decSalary)
lblBonus.Text = String.Empty
For decRate As Decimal = 0.03 To 0.06 Step 0.5
decBonus = decSalary + decRate
lblBonus.Text = lblBonus.Text & decRate.ToString("P1") & " " & decBonus.ToString("C2") & ControlChars.NewLine
Next decRate

Question 53

What is a counter-controlled loop and when is it used in a program? What statement provides the most efficient way to write a counter-controlled loop?

Question 54

Explain the difference between a looping condition and a loop exit condition.

Question 55

Write two different Do...Loop clauses that stop the loop when the value in the intAmount is less than or equal to the value in the intLimit variable. Use the Until keyword in the first clause, and use the While keyword in the second clause.

Question 56

What is the Refresh method? Write the syntax for this method.

Question 57

Write the assignment statements needed to increment the intCount counter by 1 and update the decBalance variable by the value stored in the decOrderAmount variable.

Question 58

Case-Based Critical Thinking Questions Case 1 - XYZ Solutions
You have just started working for XYZ Solutions as a programmer. Your first assignment is to review and correct various code so that you can become familiar with the company's programs.
The following code in a different program is not working properly. The message should display the value of the intCounter variable if the intCounter variable contains a balance that is less than or equal to 15. The message does not display. What mistake did the previous programmer make?
IntCounter = 1
Do Until intCounter
MessageBox.Show(intCounter)
IntCounter += 1
Loop

A) The counter is not initialized.
B) The While keyword should be used instead of the Until keyword.
C) The counter is not incrementing.
D) intCounter += 1 should be changed to intCounter = intCounter + 1 .

Question 59

What is a counter? What does it mean to initialize and update a counter in a program?

Question 60

Explain the difference between using the keywords While and Until within a Do...Loop statement.