Deck 4: Control Structures I: Selection

Question 1

The symbol >= is a logical operator.

Answer 1

False

Question 2

Suppose that you have the following code. int num = 10; if (num > 10) System.out.println(num); else System.out.println(num + 5); The output of this code is 5.

Answer 2

False

Question 3

The operators = and == have the same order of precedence.

Answer 3

False

Question 4

A computer program will recognize both = and == as the equality operator.

Question 5

A program uses selection to implement a branch.

Question 6

In Java, case and switch are reserved words, but break is not a reserved word.

Question 7

Suppose x = 10 and y = 20. The value of the expression ((x >= 10) && (y <= 20)) is true.

Question 8

Including a semicolon before the action statement in a one-way selection causes a syntax error.

Question 9

Suppose that the input is 6 and console is a Scanner object initialized to the standard input device. Consider the following code. int alpha = 7; int beta = console.nextInt(); switch (beta) {case 5: alpha = alpha + 1; case 6: alpha = alpha + 2; case 7: alpha = alpha + 3; default: alpha = alpha + 5;} System.out.print(alpha); The output of this code is 9.

Question 10

The expression !(x <= 0) is true only if x is a positive number.

Question 11

=! is a relational operator.

Question 12

In Java, || has a higher precedence than &&.

Question 13

All switch structures include default cases.

Question 14

Suppose that you have the following statements. int score; String grade; if (score >= 65) grade = "pass"; else grade = "fail"; If score is equal to 75, the value of grade is pass.

Question 15

Suppose P and Q are logical expressions. The logical expression P && Q is false if both P and Q are false.

Question 16

In Java, !, &&, and || are called logical operators.

Question 17

All switch cases include a break statement.

Question 18

Suppose P and Q are logical expressions. The expression P || Q is true if both P and Q are true.

Question 19

The expression 'A' <= 'B' evaluates to false while the expression 'A' < 'B' evaluates to true.

Question 20

When one control statement is located within another, it is said to be a controlled statement.

Question 21

The execution of a break statement in a switch statement terminates the switch statement.

Question 22

The method compareTo is part of the class String.

Question 23

Suppose str1 and str2 are String variables. The expression (str1 == str2) determines whether str1 and str2 point to the same String object.

Question 24

Which of the following is not a logical operator?

A) !
C) !=
B) ||
D) &&

Question 25

Two-way selection in Java is implemented using ____.

A) if statements
C) if...else statements
B) for loops
D) sequential statements

Question 26

Which of the following will cause a syntax error?

A) (10 < num) && (num < 30)
C) 10 < num && num < 25
B) 10 < num < 20
D) num > 10 && num < 40

Question 27

After the execution of the following code, what will be the value of num if the input values are 0 3? (Assume that console is a Scanner object initialized to the standard input device.) int num = console.nextInt(); if (num > 0) num = num + 13; else if (num >= 3) num = num + 15;

A) 0
C) 13
B) 3
D) 15

Question 28

What is the value of the expression above?

A) true
C) x
B) false
D) It cannot be determined.

Question 29

Suppose that you have the following statements. String str1 = "cat"; String str2 = "cats"; The statement str1.equals(str2); is true.

Question 30

What is the output of the following Java code? int x = 0; if (x > 0) System.out.println("positive "); System.out.println("zero "); System.out.println("negative");

A) zero
C) zero negative
B) negative
D) positive zero negative

Question 31

Which of the following is NOT a relational operator in Java?

A) <>
C) ==
B) <=
D) >

Question 32

The output of the Java code: int alpha = 5; int beta = 4; switch (beta) {case 2: alpha = alpha + 2; case 4: alpha = alpha + 4; break; case 6: alpha = alpha + 6; default: alpha = alpha + 10;} System.out.print(alpha); is: 9

Question 33

Based on the code above, what is the value of y if x = 4?

A) 2
C) 6
B) 4
D) 8

Question 34

Based on the code above, which part of the expression is not evaluated?

A) 2.5 >= 7
C) 2.5 >= 7 || 4 < y
B) 4 < y
D) 4 <= 8

Question 35

Which of the following is a relational operator?

A) =
C) !
B) ==
D) &&

Question 36

What does >= mean?

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

Question 37

Suppose that x is an int variable. Which of the following expressions always evaluates to false?

A) (x > 0) || (x <= 0)
C) (x > 0) && ( x <= 0)
B) (x > 0) || (x == 0)
D) (x >= 0) && (x == 0)

Question 38

Which of the following has the highest value?

A) '-'
C) 'H'
B) '5'
D) 'b'

Question 39

In a ____ control structure, the computer executes particular statements depending on some condition(s).

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

Question 40

Which of the following will cause a syntax error, if you are trying to compare x to 5?

A) if (x == 5)
C) if (x <= 5)
B) if (x = 5)
D) if (x >= 5)

Question 41

Based on the code above, what is the value of y if x = 5?

A) 2
C) 6
B) 4
D) 8

Question 42

Suppose that you have the following code: int sum = 0; int num = 8; if (num < 0) sum = sum + num; else if (num > 5) sum = num + 15; After this code executes, what is the value of sum?

A) 0
C) 15
B) 8
D) 23

Question 43

If str1 is "Hello" and str2 is "Hi", which of the following could not be a result of str1.compareTo(str2);?

A) -9
C) -1
B) -5
D) 1

Question 44

Based on the code above, what is the value of y if x = 9?

A) 2
C) 6
B) 4
D) 8

Question 45

Based on the code above, what is the value of y if x = 1?

A) 2
C) 6
B) 4
D) 8

Question 46

Based on the code above, what is the value of x?

A) 1
C) 5
B) 3
D) 12

Question 47

Based on the code above, what is the output if lastInitial = 'E'?

A) section 2
C) section 4
B) section 3
D) section 5

Question 48

Based on the code above, what is the output if lastInitial = 'C'?

A) section 1
C) section 3
B) section 2
D) section 5

Question 49

What is the output of the following Java code? int x = 57; int y = 3; switch (x % 9) {case 0: case 1: y++; case 2: y = y - 2; break; case 3: y = y + 2; case 4: break; case 5: case 6: y = y + 3;} System.out.println(y);

A) 2
C) 6
B) 5
D) 57

Question 50

The conditional operator ?: takes ____ arguments.

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