Cs131 Midterm

What does the following C++ expression evaluate to? 6 - 6 / 3 + 3

7

The ________ operator is used in C++ to test for equality.

==

a variable is?

A storage location in the computer's memory that can hold a piece of data

The following 4 lines of C++ code, use strings. string firstName; // Define a string object char lastName[7]; // Define a C-string firstName = "Abraham"; // Assign a value to the string object lastName = "Lincoln"; // Assign a value to the C-string

A. The 2 string definitions are correct, but the 2 assignment statements are wrong. B. The string object is defined incorrectly because no size is given for it. C. The C-string is assigned a value correctly, but the string object is not. D. All 4 lines of code are correct. Answer The string object is assigned a value correctly, but the C-string is not.

Two different variables in the same program may have the same name

A. if the second one is never declared. B. if they always hold different values. C. if the second one is initialized with a different value than the first one. D. never. A program cannot have two variables with the same name. Answer if they have different scope.

The statement cout << setw(4) << num4 << " ";

A. outputs the value of num4 rounded to 4 decimal places. B. outputs the first 4 digits of the number stored in num4. C. outputs "setw(4)" before the value in the variable num4. D. outputs the value stored in num4 four times. Answer does none of above.

Which of the following statements about named constants is/are true?

A.The initial value of a named constant, cannot be changed during the program execution. B.The identifier name of a named constant can only contain capital letters and underscores. C. A named constant must be initialized with a value at the time it is declared. Answer Statements A and C are true, but B is not.

If s1 and s2 are string objects, s1 == s2 is true when

A.s1 = "dog" and s2 = "DOG". B.s1 = "cat" and s2 = "cat ". C. s1 = "lion" and s2 = "lioness". D. None of these because string objects cannot be compared with relational operators. Answer None of these because in each case one or more characters in the strings have different ASCII codes.

A software package that includes a text editor, compiler, debugger, and assorted utilities for creating, testing, and running software is called

Aa software utility package (SUP). B. a low-level programming language. C. an operating system. D. a high-level programming language. Answer none of the above.

What will the following statement do if x equals 17 and answer = 20? answer = x > 100 ? 0 : 1;

Assign 1 to answer.

High-level programming languages include

C++ and JavaScript. C++ and Java. C++ and Visual Basic.

________ is an example of volatile memory, used for temporary storage while a program is running.

RAM

Which of the following is an example of a secondary storage device?

a hard disk drive a DVD a USB flash drive a CD

Even when there is no power to the computer, data can be held in

a secondary storage device.

A storage location in the computer's memory that can hold a piece of data is called

a variable.

In the C++ statement pay = rate * hours; the * symbol is an example of

an operator.

A flag is a variable, usually of data type ________, that signals whether or not some condition exists.

bool

The ________ object causes data to be input from the keyboard.

cin

To use the sqrt() function, or other mathematical library functions, you must #include the ________ header file in your program.

cmath

True/False: A switch statement branches to a particular block of code depending on the value of a numeric (i.e. integer or floating-point) variable or constant.

false

True/False: Executable code is computer code that contains no errors.

false

True/False: If the sub-expression on the left side of an && operator is true, the expression on the right side will not be checked.

false

True/False: If the value of dollars is 5.0, the following statement will output 5.00 to the monitor: cout << fixed << showpoint << setprecision(4) << dollars << endl;

false

True/False: In C++, the 5 basic arithmetic operators are addition (+), subtraction (-), multiplication (*), division (/), and exponentiation (^).

false

True/False: Most modern computers can understand and execute pseudocode.

false

True/False: Relational operators connect two or more relational expressions into one, or reverse the logic of an expression.

false

True/False: The cin object lets the user enter a string that contains embedded blanks.

false

True/False: The following C++ test checks if the variable child is in the range 3-12. if (child >= 3 && <= 12)

false

True/False: The following pair of C++ statements will cause 3.5 to be output. double number = 7 / 2; cout << number;

false

True/False: The following statement s will not print anything. x = 5; if (x < 5) cout << "Hello "; cout << "world \n";

false

True/False: The following statement sets the value of total to -3. total -= 3;

false

True/False: The setw manipulator is used to set the precision of a number.

false

True/False: When a C++ expression is evaluated, binary operations are performed before unary operations.

false

True/False: When an operator has two operands of different data types, C++ always converts them both to double before performing the operation.

false

The ________ statement executes one statement, or block of statements, if a condition is true and skips it, doing nothing, if the condition is false.

if

The ________ statement acts like a chain of if statements. Each performs its test, one after the other, until one of them is found to be true.

if/else if

When a program lets the user know that an invalid menu choice has been made, this is an example of

input validation.

Three primary activities of a typical program are

input, processing, and output.

IDE stands for

integrated development environment.

Words with a special meaning that may be used only for their intended purpose are known as

keywords.

Mistakes that allow a program to run, but cause it to produce erroneous results are called

logic errors.

The cin object must be followed by

one or more stream extraction (>>) operators.

When an arithmetic expression contains two or more different operators, such as * and +, the order in which the operations is done is determined by

operator precedence.

When converting some algebraic expressions to C++, you may need to insert ________ and ________ that do not appear in the algebraic expression.

operators, parentheses

The expression x < y is called a(n) ________ expression.

relational

Operator associativity is either left to right or

right to left.

A ________ is a complete instruction that causes the computer to perform some action.

statement

The programs that control and manage the basic operations of a computer are generally referred to as

system software.

A software package that includes a text editor, compiler, debugger, and assorted utilities for creating, testing, and running software is called

the answer will be none of the above

The programmer usually enters source code into a computer using

the answer will be none of the above

Internally, the central processing unit (CPU) consists of two parts:

the arithmetic and logic unit (ALU) and the control unit.

The default section of a switch statement performs a similar task as the ________ portion of an if/else if statement.

trailing else

True/False: Assuming moreData is a Boolean variable, the following two tests are logically equivalent. if (moreData == true) if (moreData)

true

True/False: If a new value is stored in a variable, it replaces whatever value was previously there.

true

True/False: In C++ an expression that evaluates to 5, -5, or for that matter anything other than 0, is considered true by an if statement.

true

True/False: Relational expressions and logical expressions are both Boolean, which means they evaluate to true or false.

true

True/False: Syntax involves rules that must be followed when writing a program.

true

True/False: The following statement sets sum1, sum2, and sum3 all to zero. sum1 = sum2 = sum3 = 0;

true

True/False: The following two expressions evaluate to the same thing: c + a * b c + (a * b)

true

What will the following expression evaluate to? !( 6 > 7 || 3 == 4)

true

A variable definition always specifies the name of a variable and tells

what type of data it can hold.

The ________ operator is known as the logical OR operator.

||