Deck 4: Control Structures I Selection

Question 1

Which of the following expressions correctly determines that x is greater than 10 and less than 20?

A) 10 < x < 20
B) (10 < x < 20)
C) 10 < x && x < 20
D) 10 < x || x < 20

Answer 1

C

Question 2

In C++, both ! and != are relational operators.

Answer 2

False

Question 3

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

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

Answer 3

A

Question 4

Which of the following operators has the highest precedence?

A) !
B) *
C) %
D) =

Question 5

The result of a logical expression cannot be assigned to an int variable, but it can be assigned to a bool variable.

Question 6

The operators !, &&, and || are called relational operators.

Question 7

Which of the following is a relational operator?

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

Question 8

Which of the following is the "not equal to" relational operator?

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

Question 9

In C++, the operators != and == have the same order of precedence.

Question 10

A control structure alters the normal sequential flow of execution in a program.

Question 11

What does <= mean?

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

Question 12

The expression (x >= 0 && x <= 100) evaluates to false if either x < 0 or x >= 100.

Question 13

Suppose x is 5 and y is 7. Choose the value of the following expression: (x != 7) && (x <= y)

A) false
B) true
C) 0
D) null

Question 14

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

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

Question 15

If the expression in an assert statement evaluates to true, the program terminates.

Question 16

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

Question 17

A compound statement functions as if it was a single statement.

Question 18

In C++, && has a higher precedence than ||.

Question 19

You can use either a(n) ____ or a ____ to store the value of a logical expression.

A) float, double
B) char, string
C) int, bool
D) float, string

Question 20

Which of the following operators has the lowest precedence?

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

Question 21

For a program to use the assert function, it must include which of the following?

A) #include
B) #include
C) #include
D) #include NDEBUG

Question 22

The term ____________________ describes a process in which the computer evaluates a logical expression from left to right and stops as soon as the value of the expression is known.

Question 23

What is the value of x after the following statements execute? int x;
X = (5 <= 3 && 'A' < 'F') ? 3 : 4

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

Question 24

Which of the following will cause a logical error if you are attempting to compare x to 5?

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

Question 25

Putting a semicolon after the parentheses following the expression in an if statement (that is, before the statement) is a(n) ____________________ error.

Question 26

Once an input stream enters a(n) ____________________ state, all subsequent input statements associated with that input stream are ignored, and the computer continues to execute the program, which produces erroneous results.

Question 27

The value of the expression 7 + 8 <= 15 is ____________________.

Question 28

What is the output of the following C++ code? int x = 35;
Int y = 45;
Int z;
If (x > y)
Z = x + y;
Else
Z = y - x;
Cout << x << " " << y << " " << z << endl;

A) 35 45 80
B) 35 45 10
C) 35 45 -10
D) 35 45 0

Question 29

Consider 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 "____________________".

Question 30

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

A) blocked
B) compound
C) nested
D) closed

Question 31

Assume you have three int variables: x = 2, y = 6, and z. Choose the value of z in the following expression: z = (y / x > 0) ? x : y;.

A) 2
B) 3
C) 4
D) 6

Question 32

The ____________________ of relational and logical operators is said to be from left to right.

Question 33

What is the output of the following C++ code?

A) 2
B) 5
C) 8
D) 10

Question 34

You can disable assert statements by using which of the following?

A) #include
B) #define
C) #clear NDEBUG
D) #define NDEBUG

Question 35

Which of the following will cause a logical error if you are attempting to compare x to 5?

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

Question 36

What is the output of the following code? char lastInitial = 'S';
Switch (lastInitial)
{
Case 'A':
Cout << "section 1" <Break;
Case 'B':
Cout << "section 2" <Break;
Case 'C':
Cout << "section 3" <Break;
Case 'D':
Cout << "section 4" <Break;
Default:
Cout << "section 5" <}

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

Question 37

Suppose found = true and num = 6. The value of the expression (!found) || (num > 6) is ____________________.

Question 38

In a switch statement, if the value of the expression does not match any of the case values, the statements following the ____________________ label execute.

Question 39

The value of the expression 6 < 5 || 'g' > 'a' && 7 < 4
is ____________________.

Question 40

Putting ____________________ in front of a logical expression reverses the value of that logical expression.