1) Which of the following loops executes the statements inside the loop before checking the condition?

a) for
b) while
c) do
d) do-for

2) How many times will the following loop run?

int i = 0;
while (i < 10)
{
System.out.println(i);
i++;
}

a) 0
b) 8
c) 9
d) 10

3) What is the output of the code snippet given below?

int i = 0;
while (i != 9)
{
System.out.println("" + i);
i = i + 2;
}

a) No output
b) 0 2 4 6 8
c) 10 12 14 16 18 …. (infinite loop)
d) 0 2 4 6 8 10 12 14 …. (infinite loop)

4) How many times does the code snippet given below display "Loop Execution"?

int i = 1;
while (i != 10)
{
System.out.println ("Loop Execution");
i++;
}

a) Infinite times
b) 8 times
c) 9 times
d) 10 times

5) What is the output of the code fragment given below?

int i = 0;
int j = 0;
while (i < 27)
{
i = i + 2;
j++;
}
System.out.println("j=" + j);

a) j=27
b) j=12
c) j=13
d) j=14

6) What is the output of the following code snippet?

int i = 1;
while (i < 10)
{
System.out.print(i + " ");
i = i + 2;
if (i == 5)
{
i = 9;
}
}

a) 1 3 5
b) 1 3 9
c) 1 3 5 7 9
d) 1 3 5 9

9) Which error type does the "off-by-one" error belong to?

a) Syntax error
b) Compile-time error
c) Run-time error
d) Infinite loop

10) How many times does the following code fragment display "Hi"?

int i = 10;
while (i >= 0)
{
System.out.println("Hi");
i--;
}

a) 9 times
b) 10 times
c) 11 times
d) 12 times

11) What is the output of the following code fragment?

int i = 1;
int sum = 0;
while (i <= 11)
{
sum = sum + i;
i++;
}
System.out.println("The value of sum is " + sum);

a) The value of sum is 65
b) The value of sum is 66
c) The value of sum is 55
d) The value of sum is 56

12) How many times does the loop execute in the following code fragment?

int i;
for (i = 0; i < 50; i = i + 4)
{
System.out.println(i);
}

a) 11
b) 12
c) 13
d) 14

15) Which loop does not check a condition at the beginning of the loop?

I. The do loop
II. The while loop
III. The for loop

a) I and II
b) I and III
c) I only
d) III only

20) What is the sentinel value in the following code snippet?

public static void main(String[] args)
{
int age = 0;
int sumOfAges = 0;
int stop = 1;
Scanner reader = new Scanner(System.in);
System.out.println("Enter an age (-1 to stop): ");
age = reader.nextInt();
while (age != -1)
{
sumOfAges = sumOfAges + age;
System.out.println("Enter an age (-1 to stop): ");
age = reader.nextInt();
}
System.out.println("Sum of ages " + sumOfAges);
return 0;
}

a) 0
b) 1
c) 2
d) -1

21) See text document.

22) What will be the output of the following code snippet?

boolean token = false;
while (token)
{
System.out.println("Hello");
}

a) “Hello” will be displayed infinite times.
b) No output because of compilation error.
c) No output after successful compilation.
d) “Hello” will be displayed only once.

23) What will be the output of the following code snippet?

boolean token = false;
do
{
System.out.println("Hello");
}
while (token);

a) “Hello” will be displayed infinite times.
b) No output because of compilation error.
c) No output after successful compilation.
d) “Hello” will be displayed only once.

24) What is the output of the following code snippet?

int i = 1;
while (i <= 10)
{
System.out.println("Inside the while loop");
i = i + 10;
}

a) No output because of compilation error.
b) “Inside the while loop” will be displayed 10 times.
c) No output after successful compilation.
d) “Inside the while loop” will be displayed only once.

25) What is the outcome of the following code snippet?

boolean val1 = true;
boolean val2 = false;
while (val1)
{
if (val1)
{
System.out.println("Hello");
}
val1 = val2;
}

a) No output will be displayed because of compilation error.
b) “Hello” will be displayed only once.
c) “Hello” will be displayed infinite times.
d) No output will be displayed even after successful compilation of the code snippet.

26) How many times does the code snippet below display "Hello"?

int i = 0;
while (i != 15)
{
System.out.println("Hello");
i++;
}

a) Infinite times
b) 14 times
c) 15 times
d) 16 times

29) What is the result when the following code is run?

double x = 1;
double y = 1;
int i = 0;
do
{
y = x / 2;
x = x + y;
i = i + 1;
}
while (x < 2.5);
System.out.print(i + " ");

a) 1
b) 2
c) 3
d) 4

30) What will be the range of the random numbers generated by the following code snippet?

int r1 = (int) (Math.random() * 50) + 1;

a) Between 1 and 49
b) Between 0 and 50
c) Between 0 and 49
d) Between 1 and 50

32) Given the following code snippet, what should we change to have 26 alphabet characters in the string str?

String str = "";
for (char c = 'A'; c < 'Z'; c++)
{
str = str + c;
}

a) int c = 'A'
b) str = c + str;
c) c <= 'Z'
d) Must change to use a do loop

33) What is the output of the code snippet given below?

String s = "abcde";
int i = 1;
while (i < 5)
{
System.out.print(s.substring(i, i + 1));
i++;
}

a) No output
b) abcd
c) abcde
d) bcde

34) What is the output of the code snippet given below?

String s = "abcde";
int i = 1;
do
{
if (i > 1)
{
System.out.print(s.substring(i, i + 1));
}
}
while (i < 5);

a) No output
b) No output (infinite loop)
c) abcde
d) bcde

35) What is the output of the code snippet given below?

String s = "12345";
int i = 1;
while (i < 5)
{
System.out.print(s.substring(i, i + 1));
i++;
}

a) No output
b) 1234
c) 12345
d) 2345

36) What is the output of the code snippet given below?

String s = "12345";
int i = 1;
do
{
if (i > 1)
{
System.out.print(s.substring(i, i + 1));
}
}
while (i < 5);

a) No output
b) No output (infinite loop)
c) 12345
d) 2345

37) Which of the following activities can be simulated using a computer?

I. Waiting time in a line at a restaurant
II. Tossing a coin
III. Shuffling cards for a card game

a) I only
b) II only
c) I and II only
d) I, II, and III

38) What is the data type of the number generated by the Math.random() function?

a) double
b) float
c) int
d) String

39) What is the output of the code fragment given below?

int i = 0;
int j = 0;
while (i < 125)
{
i = i + 2;
j++;
}
System.out.println(j);

a) 0
b) 62
c) 63
d) The code fragment displays no output because it does not compile.

40) What is the output of the following code snippet?

int i = 1;
while (i < 20)
{
System.out.print(i + " ");
i = i + 2;
if (i == 15)
{
i = 19;
}
}

a) 1 3 5 7 9 11 13 15 17 19
b) 1 3 5 7 9 11 13 19
c) 1 3 5 7 9 11 13 15 17
d) 1 3 5 7 9 11 13 17 19

42) What is the output of the following code fragment?

int i = 1;
int sum = 0;
while (i <= 15)
{
sum = sum + i;
i++;
}
System.out.println("The value of sum is " + sum);

a) The value of sum is 0
b) The value of sum is 105
c) The value of sum is 120
d) The value of sum is 136

44) Which of the following is considered a loop with a bound that could be problematic?

a) for (i = 1; i != n; i++)
b) for (years = n; years < 0; years--)
c) for (i = 1; i <= n; i++)
d) for (int i = 1; i <= 10; i++)

45) In the __________ loop header, you can include multiple update expressions, separated by commas, but it is not recommended.

a) do
b) while
c) for
d) do

46) What values does counter variable i assume when this loop executes?

for (int i = 20; i >= 2; i = i - 6)
{
System.out.print(i + ",");
}

a) 20, 14, 8, 2
b) 20, 14, 8, 2, –4
c) 20, 14, 8
d) 14, 8, 2

47) Insert a statement that will correctly terminate this loop when the end of input is reached.

boolean done = false;
while (!done)
{
String input = in.next();
if (input.equalsIgnoreCase("Q"))
{
__________
}
else
{
double x = Double.parseDouble(input);
data.add(x);
}
}

a) stop;
b) done = 1;
c) exit;
d) done = true;

48) What is the output of the code snippet given below?

String s = "abcdefghijkl";
int i = 1;
do
{
if (i > 2)
{
System.out.print(s.substring (1, i));
}
i++;
}
while (i < 5);

a) abcd
b) bcde
c) bcbcd
d) cdef

50) What does the following code do?

int sum = 0;
final int count = 1000;
for (int i = 1; i <= count; i++)
{
sum = sum + (int) (Math.random() * 101);
}
System.out.println(sum / count);

a) It simulates the outcome of throwing a coin.
b) It calculates the average of 1000 random numbers between 0 and 100.
c) It performs Monte Carlo simulation of fluid dynamics.
d) It calculates the average of 1000 random numbers between 1 and 101.

51) See text document.

52) See text document.

53) What is the output of the following code snippet?

int f1 = 0;
int f2 = 1;
int fRes;
System.out.print(f1 + " ");
System.out.print(f2 + " ");
for (int i = 1; i < 10; i++)
{
fRes = f1 + f2;
System.out.print(fRes + " ");
f1 = f2;
f2 = fRes;
}
System.out.println();

a) 0 1 5 7 9 11 13 15 17 19
b) 0 1 1 2 3 5 8 13 21 34
c) 0 1 4 6 8 10 12 14 16 18
d) 0 1 6 7 9 12 14 17 19 21

56) What is the output of the following code snippet?

int counter = 1;
for (double i = 0.01; i <= 1.0; i = i + 0.01)
{
counter++;
}
System.out.println(counter);

a) 100
b) 49.50
c) 60.5
d) 10

60) Which of the following loops executes exactly 10 times?

a) for (int i = 0; i <= 10; i++) { }
b)
int i = 0;
boolean found = false;
do
{
i++;
if (i % 10 == 0)
{
found = true;
}
}
while (i < 10 && !found);
c)
int i = 0;
while (i <= 10)
{
i++;
}
d) for (int i = 1; i <= 10; i++)

61) How many times does the following loop execute?

for (double d = 1; d != 10; d++)
{
d = d / 3;
System.out.print(d + " ");
}

a) 10
b) 9
c) 8
d) An infinite number of times

64) Suppose that a program asks a user to enter multiple integers, either positive or negative, to do some calculation. The data entry will stop when the user enters a certain value to indicate the end of the data. What value should the code use as the sentinel?

a) 0
b) -1
c) 999
d) An alphabetic character

65) Which of the following statements expresses why the following code is considered bad form?

for (rate = 5; years-- > 0; System.out.println(balance))
. . .

I. Unrelated expressions in loop header
II. Doesn't match expected for loop idiom
III. Loop iteration is not clear

a) II and III only
b) I and II only
c) I and III only
d) I, II, and III

66) Which of the following is considered a loop with a problematic condition?

a) for(i = 1; i != n; i++)
b) for (years = n; years > 0; years++)
c) for(i = 1; i <= n; i++)
d) for (int i = 20; i >= 10; i--)

67) How do you fix this code snippet to make it print out the sum when the user enters Q?

System.out.print("Enter a value, Q to quit: ");
double sum = 0;
Scanner in = new Scanner(System.in);
boolean hasData = true;
do
{
double value = in.nextDouble();
sum = sum + value;
System.out.print("Enter a value, Q to quit: ");
}
while (in.hasNext());
System.out.println("sum " + sum);

a) while (in.hasData());
b) while (!in.hasEnded());
c) while (in.hasNextDouble());
d) while (hasData);

68) What is the output of this code snippet?

String str = "ABCabc";
char ch;
int i = 0;
while (i < str.length())
{
ch = str.charAt(i);
if (Character.isLowerCase(ch))
{
System.out.print(i + " ");
}
else
{
i++;
}
}

a) 3 4 5
b) 3
c) 3 3 3 3 3 ... (infinite loop)
d) 0 1 2

72) Which of the following loop(s) could possibly not enter the loop body at all?

I. for loop
II. while loop
III. do loop

a) I only
b) I and II only
c) II and III only
d) I and III only

73) Which of the following loop(s) should be used when you need to ask a user to enter one data item and repeat the prompt if the data is invalid?

I. for loop
II. while loop
III. do loop

a) I only
b) I and II
c) III only
d) II only

74) Which of the loop(s) test the condition after the loop body executes?

I. for loop
II. while loop
III. do loop

a) I only
b) II only
c) III only
d) II and III

75) When hand-tracing the loop in the code snippet below, which variables are important to evaluate?

int i = 10;
int j = 5;
int k = -10;
int sum = 0;
while (i > 0)
{
sum = sum + i + j;
i--;
System.out.println("Iteration: " + i);
}

a) The variables i and j
b) The variables i and sum
c) The variables i, j, and k
d) The variables j and k

76. When hand tracing, drawing a line through the value stored in a variable means that

a) The value stored there has changed to something new
b) The variable is the wrong data type for the code being executed
c) The expression being evaluated uses that variable
d) The variable must be inside a loop

77. When hand-tracing a portion of code, which statement about Boolean conditions is true?

a) They typically are too complex to be evaluated.
b) They do not need to be monitored because their result usually is not stored in a variable.
c) It is rare to encounter a Boolean condition.
d) They are crucial to evaluate since they determine if-statement conditions and looping.

79. The process of hand-tracing code is valuable because

a) It is usually faster than just running the code.
b) It is the best way to design an algorithm.
c) You must already have a working program in order to do it.
d) It gives valuable insight that you do not get by running the code.

84) What will be the result of running the following code fragment?

int year = 0;
double rate = 5;
double principal = 10000;
double interest = 0;
while (year < 10)
{
interest = (principal * year * rate) / 100;
System.out.println("Interest " + interest);
}

a) The code fragment will display the interest calculated for nine years.
b) The code fragment will continue to display the calculated interest forever because the loop will never end.
c) The code fragment will not display the calculated interest and halt abruptly.
d) The code fragment will not display any output because it will not compile.

85) See text document.

87) What changes do you need to make in the following code snippet to display “Let us learn Java” exactly 10 times?

int i = 0;
while (i <= 10)
{
System.out.println("Let us learn Java");
i++;
}

a) while (i < 9)
b) while (i < 11)
c) while (i < 12)
d) int i = 1;

88) How many times is the text “Let's have fun with Java.” printed when this code snippet is run?

int i = 0;
do
{
System.out.println("Let's have fun with Java.");
i++;
if (i % 2 == 0)
{
i = 10;
}
}
while (i <= 10);

a) 1
b) 2
c) 3
d) 10

93) Which of the following statements is correct about a sentinel?
a) A sentinel is a value that creates a bridge between a data set and unrelated input.
b) A sentinel is a value that is part of the data to be processed by the program.
c) A sentinel is a value that terminates a program.
d) A sentinel is a value that indicates the end of an input sequence.