Deck 6: Looping

Question 1

It is important that the loop control ____ be altered within the body of the loop.

A) value
B) variable
C) constant
D) argument

Answer 1

B

Question 2

Before entering a loop, the first input statement, or ____, is retrieved.

A) empty body
B) posttest loop
C) loop body
D) priming read

Answer 2

D

Question 3

A counted loop is the same as an indefinite loop.

Answer 3

False

Question 4

Many seasoned programmers start counter values at 1 because they are used to doing so when working with arrays.

Question 5

Making a comparison to 0 is slower than making a comparison to any other value.

Question 6

Use a(n) ____ loop to execute a body of statements continually as long as the Boolean expression that controls entry into the loop continues to be true .

A) empty
B) while
C) definite
D) control

Question 7

Programmers rarely use indefinite loops when validating input data.

Question 8

When nesting loops, the variable in the outer loop changes more frequently.

Question 9

A(n) ____ is a kind of indefinite loop.

A) counter-controlled
B) event-controlled
C) initialized
D) validating

Question 10

You can use virtually any number of nested loops; however, at some point, your machine will no longer be able to store all the necessary looping information.

Question 11

On many keyboards, the Break key is also the ____ key.

A) Pause
B) Esc
C) Delete
D) Ctrl

Question 12

You can initialize one or more variables in the first section of a  for  statement.

Question 13

The statements that make up a loop body will continue to execute as long as the expression value remains false.

Question 14

Which is an infinite loop?

A) loopCount = 5; while(loopCount > 3);
{
   System.out.println("Hello");
   loopCount = loopCount - 1;
}
B) loopCount = 1; while(loopCount < 3);
{
   System.out.println("Hello");
}
C) loopCount = 4; while(loopCount < 3);
{
   System.out.println("Hello");
   loopCount = loopCount + 1;
}
D) loopCount = 1; while(loopCount < 3);
{
   System.out.println("Hello");
   loopCount = loopCount + 1;
}

Question 15

In order to improve loop performance, it's important to make sure the loop does not include unnecessary operations or statements.

Question 16

A ____ is a structure that allows repeated execution of a block of statements.

A) body
B) Boolean expression
C) loop
D) loop control

Question 17

A loop controlled by the user is a type of ____ loop.

A) indefinite
B) definite
C) counter-controlled
D) incrementing

Question 18

____ is the process of ensuring that a value falls within a specified range.

A) Value checking
B) Data integrity
C) Validating data
D) Syntax checking

Question 19

A loop that never ends is called a(n) ____ loop.

A) definite
B) infinite
C) while
D) for

Question 20

Shortcut operators are a programmer's only choice when incrementing or accumulating a variable's value.

Question 21

A(n) ____ loop is a special loop that is used when a definite number of loop iterations is required.

A) while
B) for
C) else
D) do…while

Question 22

What is wrong with the following code? x=1;
While (x<5);
 { System.out.println (x);
   x++;
}

A) Syntax error in the println method
B) Incorrect use of prefix increment operator
C) Semicolon at the end of the while expression
D) Incorrect initialization

Question 23

The ____ loop is the posttest loop used in Java.

A) for
B) counter-controlled
C) while
D) do...while

Question 24

Assume  d and x are integers: d = 5;
X = 2 * ++d;
What is the value of x ?

A) 10
B) 11
C) 12
D) 13

Question 25

With ____ loops, the order of the conditional expressions can be important.

A) nested
B) posttest
C) pretest
D) indefinite

Question 26

When creating a for loop, which statement will correctly initialize more than one variable?

A) for a=1, b=2
B) for(a=1; b=2)
C) for(a=1, b=2)
D) for(a = 1&& b = 2)

Question 27

A(n) ____ loop is one that performs no actions other than looping.

A) nested
B) do-nothing
C) indefinite
D) posttest

Question 28

One execution of any loop is called a(n) ____.

A) run
B) loop
C) prime
D) iteration

Question 29

The ____ loop checks the value of the loop control variable at the bottom of the loop after one repetition has occurred.

A) while
B) do…while
C) for
D) else

Question 30

____ is a technique that can improve loop performance by combining two loops into one.

A) Loop fusion
B) Prefix incrementing
C) Short-circuit evaluation
D) Do-nothing looping

Question 31

When you want to increase a variable's value by exactly 1, use the ____.

A) power statement
B) accumulating operator
C) binary operators
D) prefix increment operator

Question 32

In the expressions b = 8 and c = --b , what value will be assigned to the variable c ?

A) 7
B) 8
C) 9
D) 10

Question 33

You can initialize more than one variable in a for loop by placing a(n) ____ between the separate statements.

A) semicolon
B) equal sign
C) period
D) comma

Question 34

A for loop provides a convenient way to create a(n) ____ loop.

A) counter-controlled
B) posttest
C) while
D) infinite

Question 35

A(n) ____ is a body with no statements in it.

A) infinite loop
B) empty body
C) finite loop
D) event-controlled loop

Question 36

In a do…while loop, the loop will continue to execute until ____.

A) the loop control variable is true
B) the loop control variable is false
C) the user types EXIT
D) the program terminates

Question 37

Which of the following is NOT a valid method to increase a variable named score by 1?

A) ++score
B) score++
C) ++score = score + 1
D) score = score + 1

Question 38

You use a unary minus sign preceding a value to make the value ____.

A) negative
B) positive
C) valid
D) constant

Question 39

How many times will outputLabel be called? for(customer = 1; customer <= 20; ++customer)
     for(color = 1; color <= 3; ++color)
          outputLabel();

A) 0
B) 3
C) 20
D) 60

Question 40

The process of repeatedly increasing a value by some amount is known as ____.

A) checking
B) adding
C) accumulating
D) containing

Question 42

What is wrong with the following code? while (4>2)
 System.out.println ("Hi there");

A) missing curly braces
B) illegal conditional expression
C) infinite loop
D) Syntax error in the output statement

Question 47

What is the output of the following code: loopCount = 1;
While(loopCount < 3)
{
   System.out.println("Hello");
   loopCount = loopCount + 1;
}

A) Hello
B) Hello Hello
C) Hello Hello
Hello
D) HelloHello

Question 48

What is the output of the following code: for (loop = 1; loop <3; ++loop)
   System.out.print(1);
   for (loop2 = 1; loop2< 3; ++loop2)
      System.out.print(2);

A) 112222
B) 1232212322
C) 122122
D) 122212221222

Question 54

What is the output of the following code:​ loopCount = 1;
While(loopCount < 3)
   System.out.println("Hello");
   loopCount = loopCount + 1;

A) No output
B) Hello Hello
C) Hello Hello
Hello
D) This is an infinite loop

Question 58

What kind of loop is this: response = keyboard.nextInt();
While (response == 1)
{
    System.out.print ("Enter 1 to continue; 0 to stop");
    response = keyboard.nextInt();
}

A) posttest
B) definite
C) event-driven
D) counted

Question 61

Why would a loop with altered user input be considered a type of indefinite loop? Give an example.

Question 62

What would happen if a semicolon is mistakenly placed at the end of a partial statement of a while loop with a Boolean expression and with an empty body?

Question 63

Explain why an infinite loop might not actually execute infinitely.

Question 64

How could a programmer identify and escape from an infinite loop?

Question 65

​
while(count < getNumberOfEmployees())
Examine the statement above. Write the code that will result in more efficient program execution assuming the result of getNumberOfEmployees() stays the same.

Question 66

How are indefinite loops used for validating data? Why is a loop structure typically the better choice for validating data than an if statement?

Question 67

How does a for loop work?

Question 68

Describe how a loop is controlled by a Boolean expression.

Question 69

Provide a code example of a pretest loop and an example of a posttest loop.

Question 70

What are some unconventional uses of the three sections inside the parentheses of a  for loop? Show at least three examples using code.

Question 71

What is loop fusion? Write a code segment that uses loop fusion to call two methods, method1 and method2 , 10 times each.

Question 72

counterLoop = 1;
while(counterLoop < 10);
{
     System.out.println("Hello");
     counterLoop = counterLoop + 1;
}
What is the problem in the above while loop? How would you correct the problem?

Question 73

public class IncrDemo
{
    public static void main(String[] args)
    {
      int myVal, yourVal;
      myVal = 10;
      System.out.println("My initial value is " + myVal);
      yourVal = ++myVal;
      System.out.println("My new value is " + myVal);
      System.out.println("Your value is " + yourVal):
    }
}
Using the above code, describe how the three println output commands will appear. Explain the values stored in the variables during code execution.

Question 74

How are nested loops implemented in a loop structure?

Question 75

while(10 > 1)
{
   System.out.println("This prints forever.");
}
Identify the problem that exists in the above while loop.

Question 76

​What are the three sections inside the parentheses of a for loop typically used for?

Question 77

How could you rewrite the following code to have the arithmetic performed only once, even if the loop executes 1,000 times?
while (x < a + b)
// loop body