Question 1

Which formatting flag indicates that the floating-point values should be output with a thousands separator?
A)plus (+).
B)minus (-).
C)comma (,).
D)period (. ).

Accepted Answer

The comma flag (,) is used to indicate that a thousands separator should be included in the output of floating-point values.

Question 2

Which of the following statements about the break statement is false?
A)The break statement is used to exit a repetition structure early and continue execution after the loop.
B)A break statement can only break out of an immediately enclosing while,for,do…while or switch statement.
C)The break statement,when executed in a while,for or do…while,skips the remaining statements in the loop body and proceeds with the next iteration of the loop.
D)Common uses of the break statement are to escape early from a loop or to skip the remainder of a switch.

Accepted Answer

The break statement does not proceed with the next iteration of the loop; it exits the loop entirely.

Question 3

For the two code segments below:
Segment A
Int q = 5;
Switch(q)
{
Case 1:
System.out.println(1);
Case 2:
System.out.println(2);
Case 3:
System.out.println(3);
Case 4:
System.out.println(4);
Case 5:
System.out.println(5);
Default:
System.out.println("default");
}
Segment B
Q = 4;
Switch(q)
{
Case 1:
System.out.println(1);
Case 2:
System.out.println(2);
Case 3:
System.out.println(3);
Case 4:
System.out.println(4);
Case 5:
System.out.println(5);
Default:
System.out.println("default");
}
Which of the following statements is true?
A)The output for Segment A is:
Default
B)The output for Segment B is:
4
C)The output for Segment B is:
45default
D)The output for Segment A is:
5
Default

Accepted Answer

In Segment A, q is assigned a value of 5 and when the switch statement is executed, the case corresponding to 5 is executed which prints out 5. Therefore, the output for Segment A is "5".
In Segment B, q is assigned a value of 4 and when the switch statement is executed, the case corresponding to 4 is executed which prints out 4. Therefore, the output for Segment B is "4".

Question 4

Which statement prints the floating-point value 123.456 right justified with a field width of 10?
A)System.out.printf("%d10.3",123.456);
B)System.out.printf("%10.3d",123.456);
C)System.out.printf("%f10.3",123.456);
D)System.out.printf("%10.3f",123.456);

Accepted Answer

The %f format specifier is used to print floating-point values in Java. To print the given value right justified with a field width of 10, we use the flag combination of "%10.3f". Here, "10" indicates the field width and ".3" specifies the number of digits to be printed after the decimal point. Using "%d" in place of "%f" would try to print the floating-point value as an integer and result in a compile error. Similarly, using "123.456d" in place of "123.456" would also result in a compile error.

Question 5

Which of the following can be used in a switch statement in the expression after keyword case?
a)a constant integral expression.
b)a character constant.
c)a String
d)an enumeration constant.
A)A and B.
B)A and C.
C)B and C.
D)All.

Accepted Answer

In a switch statement, the expression after the keyword case can be a constant integral expression, a character constant, a String, or an enumeration constant. This allows for a variety of types to be used in switch-case constructs, enhancing the flexibility of this control flow statement.

Question 6

Which of the following statements about the continue statement is true?
A)The continue statement is used to exit a repetition structure early and continue execution after the loop.
B)The continue statement is used to continue after a switch statement.
C)The continue statement does not alter the flow of control.
D)A continue statement proceeds with the next iteration of the immediately enclosing while,for,do…while statement.

Accepted Answer

The continue statement is used to skip the current iteration of the loop and proceed with the next iteration of the immediately enclosing while, for, do…while statement. It does alter the flow of control by skipping the remaining statements in the current iteration and moving to the next iteration. Statement A refers to the break statement, not continue. Statement B is incorrect as the continue statement is not used with switch statements. Statement C is also incorrect as the continue statement does alter the flow of control.

Question 7

Consider the classes below:
Public class TestA
{
Public static void main(String args[])
{
Int x = 2;
Int y = 20
Int counter = 0;
For (int j = y % x;j < 100;j += (y / x))
Counter++;
}
}
Public class TestB
{
Public static void main(String args[])
{
Int counter = 0;
For (int j = 10;j > 0;--j)
++counter;
}
}
Which of the following statements is true?
A)The value of counter will be different at the end of each for loop for each class.
B)The value of j will be the same for each loop for all iterations
C)Both (a)and (b)are true.
D)Neither (a)nor (b)is true.

Accepted Answer

The answer of Consider the classes below:
Public class TestA
{
Public static...

Question 8

Consider the code segment below.
If (gender == 1)
{
If (age >= 65)
++seniorFemales;
}
This segment is equivalent to which of the following?
A)if (gender == 1 || age >= 65)
++seniorFemales;
B)if (gender == 1 && age >= 65)
++seniorFemales;
C)if (gender == 1 AND age >= 65)
++seniorFemales;
D)if (gender == 1 OR age >= 65)
++seniorFemales;

Accepted Answer

The code segment checks if the gender is female (assuming 1 represents female) and if age is greater than or equal to 65. Therefore, the equivalent condition using logical operators is "gender == 1 && age >= 65". Option A ("gender == 1 || age >= 65") would count any female or anyone aged 65 and above, which is not equivalent. Option C has an incorrect logical operator ("AND" instead of "&&"). Option D has incorrect logical operators ("OR" instead of "&&").

Question 9

For the code segment below:
Switch(q)
{
Case 1:
System.out.println("apple");
Break;
Case 2:
System.out.println("orange");
Break;
Case 3:
System.out.println("banana");
Break;
Case 4:
System.out.println("pear");
Case 5:
System.out.println("grapes");
Default:
System.out.println("kiwi");
}
Which of the following values for q will result in kiwi being included in the output?
A)2.
B)Any integer less than 1 and greater than or equal to 4.
C)1.
D)3.

Accepted Answer

If q is any integer less than 1 or greater than or equal to 4, the switch will not match any case with a break, leading to the default case executing, which prints "kiwi".

Question 10

Which of the following will count down from 10 to 1 correctly? A)for (int j = 10;j <= 1;j++) B)for (int j = 1;j <= 10;j++) C)for (int j = 10;j > 1;j--) D)for (int j = 10;j >= 1;j--)

Accepted Answer

The correct syntax for counting down from 10 to 1 in a for loop is to initialize the counter variable to 10 (int j = 10), set the loop condition to run as long as the counter variable is greater than or equal to 1 (j >= 1), and decrement the counter variable by 1 at the end of each iteration (j--). Choice D satisfies all of these conditions correctly.

Question 11

Which of the following for-loop headers results in equivalent numbers of iterations:
a)for (int q = 1;q <= 100;q++)
b)for (int q = 100;q >= 0;q--)
c)for (int q = 99;q > 0;q -= 9)
d)for (int q = 990;q > 0;q -= 90)
A)A and B.
B)C and D.
C)A and B have equivalent iterations and C and D have equivalent iterations.
D)None of the loops have equivalent iterations.

Accepted Answer

The answer of Which of the following for-loop headers results...

Question 12

Which of the following is equivalent to this code segment?
Int total = 0;
For (int i = 0;i <= 20;i += 2)
Total += i;
A)int total = 0;
For (int i = 20;i < 0;i += 1)
Total += i;
B)int total = 0;
For (int i = 0;i <= 20;total += i,i += 2);
C)int total = 0;
For (int i = 0,i <= 20,total += i;i += 2);
D)int total = 0;
For (int i = 2;i < 20;total += i,i += 2);

Accepted Answer

This code initializes the total variable to zero and then loops through all even numbers from 0 to 20 (inclusive), adding each even number to the total. Choice B is equivalent because it initializes the total variable to zero, uses a for loop to iterate from 0 to 20 (inclusive) with a step of 2, and adds each even number to the total within the for loop.

Question 13

Counter-controlled repetition requires
A)A control variable and initial value.
B)A control variable increment (or decrement).
C)A condition that tests for the final value of the control variable.
D)All of the above.

Accepted Answer

Counter-controlled repetition requires all of the above - a control variable and initial value, a control variable increment (or decrement), and a condition that tests for the final value of the control variable. These three components work together to create a loop that repeats until the condition is no longer met.

Question 14

Which of the following will not help prevent infinite loops?
A)Include braces around the statements in a do…while statement.
B)Ensure that the header of a for or while statement is not followed by a semicolon.
C)If the loop is counter-controlled,the body of the loop should increment or decrement the counter as needed.
D)If the loop is sentinel-controlled,ensure that the sentinel value is input eventually.

Accepted Answer

Including braces around the statements in a do…while loop does not inherently prevent infinite loops; it simply organizes the code. Preventing infinite loops involves ensuring loop conditions are met or changed as needed, not merely the syntax structure.

Question 15

Which of the following statements is true?
A)Strings can be used in a switch statement's controlling expression and in its case labels.
B)Strings can be used in a switch statement's controlling expression but not in its case labels.
C)Strings cannot be used in a switch statement's controlling expression but can be used in its case labels.
D)Strings cannot be used in a switch statement's controlling expression and cannot be used in its case labels.

Accepted Answer

Strings can be used both in a switch statement's controlling expression and in its case labels. This feature was introduced in Java 7.

Question 16

The control variable of a counter-controlled loop should be declared as ________to prevent errors.
A)int.
B)float.
C)double.
D)Any of the above.

Accepted Answer

The control variable of a counter-controlled loop should be declared as int because it represents a whole number. Declaring it as float or double may cause errors or unexpected behavior since they represent decimal numbers.

Question 17

To exit out of a loop completely,and resume the flow of control at the next statement after the loop,use a _______.
A)continue statement.
B)break statement.
C)return statement.
D)Any of the above.

Accepted Answer

The break statement is used to exit out of a loop completely and resume the flow of control at the next statement after the loop. The continue statement, on the other hand, skips the current iteration of the loop and goes to the next iteration. The return statement is used to return a value from a function and terminate the function. So, the best choice is B.

Question 18

Which of the following statements about a do…while repetition statement is true?
A)The body of a do…while loop is executed only if the terminating condition is true.
B)The body of a do…while loop is executed only once.
C)The body of a do…while loop is always executed at least once.
D)None of the above.

Accepted Answer

In a do...while loop, the body is executed at least once, regardless of the terminating condition. After the first iteration, the condition is checked, and if it is still true, the loop will continue to execute.

Question 19

Consider the following two Java code segments:
Segment 1 Segment 2
Int i = 0;
For (int i = 0;i <= 20;i++)
While (i < 20){
{ System.out.println(i);
I++;}
System.out.println(i);
}
Which of the following statements are true?
A)The output from these segments is not the same.
B)The scope of the control variable i is different for the two segments.
C)Both (a)and (b)are true.
D)Neither (a)nor (b)is true.

Accepted Answer

In segment 1, the control variable i is declared outside the for loop with an initial value of 0. In segment 2, the control variable i is declared inside the while loop with no initial value. This means that the scope of the control variable i is different for the two segments. Additionally, the output from the two segments is not the same, as in segment 1 the value of i is not printed before it is incremented, while in segment 2 the value of i is printed before and after it is incremented. Therefore, both (a) and (b) are true.

Question 20

Which of the following statements about the switch statement is false?
A)You can use Strings in a switch statement's controlling expression.
B)You can use a String in a switch statement's case label.
C)You can use a comma-separated list of Strings in a switch statement's case label.
D)You cannot use a String in a switch statement's default case label.

Accepted Answer

DC) Java does not allow a comma-separated list of Strings in a switch statement's case label. Each case label must be a single value or a single expression that results in a value.D) The default case in a switch statement does not allow for any condition, including Strings. It is executed when none of the case labels match the switch expression, and it does not require or allow a value label.

Quiz 5: Control Statements: Part 2

Which formatting flag indicates that the floating-point values should be output with a thousands separator?

Which of the following statements about the break statement is false?

Which statement prints the floating-point value 123.456 right justified with a field width of 10?

Which of the following can be used in a switch statement in the expression after keyword case? a) a constant integral expression. b) a character constant. c) a String d) an enumeration constant.

Which of the following statements about the continue statement is true?

Consider the code segment below. If (gender == 1) { If (age >= 65) ++seniorFemales; } This segment is equivalent to which of the following?

Which of the following will count down from 10 to 1 correctly?

Which of the following for-loop headers results in equivalent numbers of iterations: a) for (int q = 1;q <= 100;q++) b) for (int q = 100;q >= 0;q--) c) for (int q = 99;q > 0;q -= 9) d) for (int q = 990;q > 0;q -= 90)

Which of the following is equivalent to this code segment? Int total = 0; For (int i = 0;i <= 20;i += 2) Total += i;

Counter-controlled repetition requires

Which of the following will not help prevent infinite loops?

Which of the following statements is true?

The control variable of a counter-controlled loop should be declared as ________to prevent errors.

To exit out of a loop completely,and resume the flow of control at the next statement after the loop,use a _______.

Which of the following statements about a do…while repetition statement is true?

Consider the following two Java code segments: Segment 1 Segment 2 Int i = 0; For (int i = 0;i <= 20;i++) While (i < 20) { { System.out.println(i) ; I++;} System.out.println(i) ; } Which of the following statements are true?

Which of the following statements about the switch statement is false?