Question 1

boolean found = false;
Int num;
Int square;while (!found)
{
Num = console.nextInt();
Square = num * num;
If (square > 40)
Found = true;
}The above code is an example of a(n) ____ loop.

Accepted Answer

This is a flag-controlled loop because the "found" boolean variable is being used as a flag to determine when to exit the loop.

Question 2

static final int EndVal = -1;
Int double;
Int num = console.nextInt();while (num != EndVal)
{
Double = num * 2;
System.out.println(double);
Num = console.nextInt();
}The above code is an example of a(n) ____ while loop.

Accepted Answer

This is a sentinel-controlled while loop because the loop continues to execute until the sentinel value (-1 in this case) is entered.

Question 3

1, 1, 2, 3, 5, 8, 13, 21, ...What is the tenth Fibonacci number in the sequence above?

Accepted Answer

The tenth Fibonacci number is found by adding the 9th and 8th Fibonacci numbers together (since the sequence starts with 1 and 1). The 9th Fibonacci number is 34 and the 8th Fibonacci number is 21, so 34 + 21 = 55. Therefore, the answer is C.

Question 4

Which of the following is NOT a reserved word in Java?

Accepted Answer

"loop" is not a reserved word in Java.

Question 5

Which of the following is true about a while loop?

Accepted Answer

The while loop is a pre-test loop, meaning the condition is checked before the loop body is executed. This allows for the possibility that the loop body may not execute at all if the condition is false from the beginning.

Question 6

Because a do...while loop is a post-test loop, the body of the loop may not execute at all.

Accepted Answer

A do...while loop is guaranteed to execute at least once because the condition is tested after the loop body has executed.

Question 7

If a continue statement is placed in a do...while structure, the loop-continue test is evaluated immediately after the continue statement.

Accepted Answer

In a do...while structure, the continue statement will skip to the end of the loop body and start the next iteration, but the loop condition test is evaluated at the end of the loop body, just before starting the next iteration. Therefore, the loop-continue test will be evaluated after the continue statement.

Question 8

int sum = 0;int limit = console.nextInt();
Int counter = 0;while (counter <= limit){
Entry = console.nextInt();
Sum = sum + entry;
Counter++;
}The above code is an example of a(n) ____ while loop.

Accepted Answer

This is a counter-controlled while loop because it uses a counter variable (in this case "counter") to control the number of iterations. The loop will execute "limit" number of times, which is set by the user input, and the counter variable is incremented after each iteration to keep track of the number of iterations.

Question 9

int i;for (i = 0; i <= 10; i++)
System.out.println("*");
System.out.println("!");Which of the following is the initial expression in the for loop above?

Accepted Answer

The initial expression in the for loop is "i = 0", which initializes the variable i with a value of 0.

Question 10

int i;for (i = 0; i <= 10; i++)
System.out.println("*");
System.out.println("!");Which of the following is the update expression in the for loop above?

Accepted Answer

In the for loop, the expression "i++" is the update expression because it increments the value of "i" by 1 after each iteration.

Question 11

After a break statement executes, the program continues to execute with the first statement after the structure.

Accepted Answer

This is true. When a break statement is executed inside a loop, the program will immediately exit the loop and continue executing with the statement immediately following the loop.

Question 12

What is the output of the following Java code?int num = 15;
While (num > 0)
Num = num - 3;
System.out.println(num);

Accepted Answer

The loop subtracts 3 from num in each iteration until num is no longer greater than 0. Starting from 15, it will go 12, 9, 6, 3, and finally 0, at which point the condition num > 0 is false, and it exits the loop. The last value assigned to num is 0, which is printed.

Question 13

The do...while loop has an exit condition but no entry condition.

Accepted Answer

The do...while loop first executes the code block and then checks the exit condition. Therefore, it has no entry condition.

Question 14

A break statement is legal in a while loop, but not in a for loop.

Accepted Answer

A break statement is legal in both a for loop and a while loop.

Question 15

Suppose sum and num are int variables, and the input is
20 25 10 18 -1 What is the output of the following code? (Assume that console is a Scanner object initialized to the standard input device.)sum = 0;
Num = console.nextInt();
While (num != -1)
{
If (num >= 20)
Sum = sum + num;
Else
Sum = sum - num;
Num = console.nextInt();
}
System.out.println(sum);

Accepted Answer

The code adds numbers greater than or equal to 20 and subtracts numbers less than 20. The operations are: 20 (added) + 25 (added) - 10 (subtracted) + 18 (subtracted) = 17.

Question 16

ch = inFile.next().charAt();while (inFile.hasNext())
{
System.out.println(ch);
Ch = inFile.next().charAt();
}The above code is an example of a(n) ____ loop.

Accepted Answer

The loop is controlled by the presence of the end-of-file character, which is detected using the hasNext() method. Therefore, it is an EOF-controlled loop.

Question 17

What is the value of counter after the following statements execute?counter = 1;
While (counter<30)
Counter = 2 * counter;

Accepted Answer

The loop doubles the value of counter starting from 1 until it reaches or exceeds 30. The sequence of values will be 1, 2, 4, 8, 16, 32. The loop stops when counter reaches 32, as it is the first value greater than or equal to 30.

Question 18

int i;for (i = 0; i <= 10; i++)
System.out.println("*");
System.out.println("!");Which of the following is the logical expression in the for loop above?

Accepted Answer

The logical expression in the for loop is the condition that determines whether the loop will continue to execute. In this case, it is "i <= 10". However, among the given choices, "i" is the closest representation of the logical expression.

Question 19

What is value of x after the following code executes?int x = 0;
Int i;for (i = 0; i < 5; i++)
X = 3 * x + i;

Accepted Answer

The answer of What is value of x after the...

Question 20

What is the output of the following code?int count;
Int num = 2;for (count = 1; count " ");
}
System.out.println();

Accepted Answer

The code initializes count to 1 and num to 2. The for loop increments count by 3 each iteration, and prints the value of num. The loop terminates when count is greater than or equal to 10. Therefore, the output is 5 8.

Quiz 5: Control Structures II: Repetition

boolean found = false; Int num; Int square;while (!found) { Num = console.nextInt() ; Square = num * num; If (square > 40) Found = true; }The above code is an example of a(n) ____ loop.

static final int EndVal = -1; Int double; Int num = console.nextInt() ;while (num != EndVal) { Double = num * 2; System.out.println(double) ; Num = console.nextInt() ; }The above code is an example of a(n) ____ while loop.

1, 1, 2, 3, 5, 8, 13, 21, ...What is the tenth Fibonacci number in the sequence above?

Which of the following is NOT a reserved word in Java?

Which of the following is true about a while loop?

Because a do...while loop is a post-test loop, the body of the loop may not execute at all.

If a continue statement is placed in a do...while structure, the loop-continue test is evaluated immediately after the continue statement.

int sum = 0;int limit = console.nextInt() ; Int counter = 0;while (counter <= limit) { Entry = console.nextInt() ; Sum = sum + entry; Counter++; }The above code is an example of a(n) ____ while loop.

int i;for (i = 0; i <= 10; i++) System.out.println("*") ; System.out.println("!") ;Which of the following is the initial expression in the for loop above?

int i;for (i = 0; i <= 10; i++) System.out.println("*") ; System.out.println("!") ;Which of the following is the update expression in the for loop above?

After a break statement executes, the program continues to execute with the first statement after the structure.

What is the output of the following Java code?int num = 15; While (num > 0) Num = num - 3; System.out.println(num) ;

The do...while loop has an exit condition but no entry condition.

A break statement is legal in a while loop, but not in a for loop.

ch = inFile.next() .charAt() ;while (inFile.hasNext() ) { System.out.println(ch) ; Ch = inFile.next() .charAt() ; }The above code is an example of a(n) ____ loop.

What is the value of counter after the following statements execute?counter = 1; While (counter<30) Counter = 2 * counter;

int i;for (i = 0; i <= 10; i++) System.out.println("*") ; System.out.println("!") ;Which of the following is the logical expression in the for loop above?

What is value of x after the following code executes?int x = 0; Int i;for (i = 0; i < 5; i++) X = 3 * x + i;

What is the output of the following code?int count; Int num = 2;for (count = 1; count " ") ; } System.out.println() ;