Computer Science 1 Final

What is the value of donuts after the following code executes? int donuts = 10; if (donuts = 1) donuts = 0; else donuts += 2;

0

What will the following loop display? int x = 0; while (x < 5) { cout << x << endl; x++; }

0 1 2 3 4

What is the output of the following code? int w = 98; int x = 99; int y = 0; int z = 1; if (x >= 99) { if (x < 99) cout << y << endl; else cout << z << endl; } else { if (x == 99) cout << x << endl; else cout << w << endl; }

1

What will the following program segment display? int funny = 7, serious = 15; funny = serious % 2; if (funny != 1) { funny = 0; serious = 0; } else if (funny == 2) { funny = 10; serious = 10; } else { funny = 1; serious = 1; }

1 1

What is the output of the following code segment? n = 1; for ( ; n <= 5; ) cout << n << ' '; n++;

1 1 1 ... and on forever

What is the value of donuts after the following code executes? int donuts = 10; if (donuts != 10) donuts = 0; else donuts += 2;

12

What is the output of the following segment of code if 4 is input by the user when asked to enter a number? int num; int total = 0; cout << "Enter a number from 1 to 10: "; cin >> num; switch (num) { case 1: ; case 2: total = 5; case 3: total = 10; case 4: total = total + 3; case 5: total = total + 6; case 6: total = total +4; } cout << total << endl;

13

What will the value of x be after the following statements execute? int x = 0; int y = 5; int z = 4; x = y + z * 2;

13

After the execution of the following code, what will be the value of input_value if the value 0 is entered at the keyboard at run time? cin >> input_value; if (input_value > 5) input _value = input_value + 5; else if (input_value >2) input_value = input_value + 10; else input_value = input_value +15;

15

What is the output of the following program? #include <iostream> using namespace std; void doSomething(int&); int main ( ) { int x = 2; cout << x << endl; doSomething(x); cout << x << endl; return 0; } void doSomething(int& num) { num = 0; cout << num << endl; }

2 0 0

How many times will the following loop display "Hello"? for (int i = 0; i < 20; i++) cout << "Hello!" << endl;

20

How many times will the following loop display "Hello"? for int i = 0; i <= 10; i++) cout << "Hello!" << endl;

21

Given the following code segment, what is output after "result = "? int x = 1, y = 1, z = 1; y = y + z; x = x + y; cout << "result = " << (x < y ? y : x) << endl;

3

What will the following code display? int x = 0; for (int count = 0; count < 3; count++) x += count; cout << x << endl;

3

Assuming x is 5, y is 6, and z is 8, which of the following is false? x == 5; 7 <= (x + 2); z <= 4; (1 + x) != y; z >= 8; x >= 0; x <= (y * 2);

3 and 4 are false z <= 4; (1 + x) != y;

What is the output of the following program? #include <iostream> using namespace std; void showDub(int); int main ( ) { int x = 2; showDub(x); cout << x << endl; return 0 ; } void showDub(int num) { cout << (num * 2) << endl; }

4 2

What will the following code display? int numbers[ ] = {99, 87, 66, 55, 101}; cout << numbers[3] << endl;

55

Which value can be entered to cause the following code segment to display the message "That number is acceptable." int number; cin >> number; if (number > 10 && number < 100) cout << "That number is acceptable.\n"; else cout << "That number is not acceptable.\n";

99

Look at the following statement. while (x++ < 10) Which operator is used first?

<

What will the following segment of code output if 11 is entered at the keyboard? int number; cin >> number; if (number > 0) cout << "C++"; else cout << "Soccer"; cout << " is "; cout << "fun" << endl;

C++ is fun

A local variable and a global variable may not have the same name within the same program.

False

A statement that starts with a # is called a comment.

False

Assume array1 and array2 are the names of arrays. To assign the contents of array2 to array1, you would use the following statement. array1 = array2

False

If you use a C++ key word as an identifier, your program will compile, link, but not execute.

False

The following code correctly determines whether x contains a value in the range of 0 to 100. if (x >= 0 && <=100)

False

The scope of a variable declared in a for loop's initialization expression always extends beyond the body of the loop.

False

What will be the output of the following code segment after the user enters 0 at the keyboard? int x = -1; cout << "Enter a 0 or a 1 from the keyboard: "; if (x) cout << "true" << endl; else cout << "false" << endl;

False

When a function is called, flow of control moves to the function's prototype.

False

When using the equality operator to compare integer values there will be potential round-off errors.

False

You may nest while and do-while loops, but you may not nest for loops.

False

You may not use the break and continue statements within the same set of nested loops.

False

You must furnish an argument with a function call.

False

What will the following segment of code output? int = 5; if (x = 2) cout << "This is true!" << endl; else cout << "This is false!" << endl; cout << "This is all folks!" << endl;

This is true! This is all folks!

An example of a secondary storage device is a hard drive.

True

An individual array element can be processed like any other type of C++ variable.

True

As a rule of style, when writing an if statement you should indent the conditionally-executed statements.

True

Each individual element of an array can be accessed by the array name and an element number, called a subscript.

True

Floating point constants are normally stored in memory as doubles.

True

If an array is partially initialized, the uninitialized elements will be set to zero.

True

If the sub-expression on the left side of an && operator is false, the expression on the right side will not be checked.

True

If the sub-expression on the left side of the || operator is true, the expression on the right side will not be checked.

True

It is not considered good programming practice to declare all of your variables globally.

True

One reason for using functions is to break programs into manageable units, or modules.

True

The following code correctly determines whether x contains a value out of the range of 0 through 100. if (x < 0 || x > 100)

True

Variables need to be declared before they can be used.

True

When you pass an array as an argument to a function, the function can modify the contents of the array.

True

You may use the exit( ) function to terminate a program, regardless of which control mechanism is executing.

True

You should be careful when using the equality operator to compare floating point values because of potential round-off errors.

True

A loop that is inside another loop is called

a nested loop

The while loop has two important parts: an expression that is tested for a true or false value. and:

a statement or block that is repeated as long as the expression is true.

Given that x = 2, y = 1, and z = 0, what will the following cout statement display? cout << "answer = " << (x || !y && z) << endl;

answer = 1

Input values should always be checked for:

appropriate range reasonableness division by zero, if division is taking place

Unlike regular variables, these can hold multiple values.

arrays

In C++ the = operator indicates:

assignment

Subscript numbering in C++

begins with 0

This statement causes a loop to terminate early.

break

Without this statement appearing in a switch construct, the program "falls through" all of the statements below the one with the matching case expression.

break

Functions are ideal for use in menu-driven programs. When a user selects a menu item, the program can ___________ the appropriate function.

call

This statement may be used to stop a loop's current iteration and begin the next one.

continue

In a function, you must furnish:

data type(s) of the parameters data type of the return value the name of the function names of parameter variables

These types of arguments are passed to parameters automatically if no argument is provided in the function call.

default

A function __________ contains the statements that make up the function.

definition

Look at the following function prototype. int myFunction (double); What is the data type of the function's parameter variable?

double

Local variables are initialized to zero by default.

false

If you want a user to enter exactly 20 values, which loop would be best to use?

for

This loop is a good choice when you know how many times you want the loop to iterate in advance of entering the loop.

for

An array can easily be stepped through by using a

for loop

This is a collection of statements that performs a specific task.

function

A ___________ variable is declared outside all functions.

global

If a function does not have a prototype, default arguments may be specified in the function ____________.

header

In a for statement, this expression is executed only once.

initialization

A(n) ___________ can be used to specify the starting values of an array.

initialization list

Arrays may be _________ at the time they are __________.

initialized, declared

When a program lets the user know that an invalid choice has been made, this is known as:

input validation

It is ________ to pass an argument to a function that contains an individual array element, such as numbers[3].

legal in C++

Which line in the following program contains a call to the showDub function? #include <iostream> using namespace std; void showDub(int); int main ( ) { int x = 2; showDub(x); cout << x << endl; return 0; } void showDub(int num) { cout << (num * 2) << endl; }

line 10 void showDub(x);

Which line in the following program will cause a compiler error? #include <iostream> using namespace std; int main ( ) { int number = 5; if (number >= 0 && <= 100) cout << "passed. \n"; else cout << "failed. \n"; return 0; }

line 8 if (number >= 0 && <= 100)

To pass an array as an argument to a function, pass the ___________ of the array.

name

When an if statement is placed within the conditionally-executed code of another if statement, this is known as:

nesting

The _________ is automatically appended to a character array when it is initialized with a string constant.

null terminator

A file must be _______ before data can be written to or read from it.

opened

Assuming outFile is a file stream object and number is a variable, which statement writes the contents of number to the file associated with outFile?

outFile << number;

The do-while loop is considered a(n) ___________ loop.

post-test

Which of the following is not one of the five major components of a computer system? - preprocessor - cpu - main memory - i/o devices - secondary storage

preprocessor

A two-dimensional array can be viewed as _________ and __________.

rows, columns

Given the following declaration, where is 77 stored in the scores array? int scores[ ] = {83, 62, 77, 97};

scores [2]

The value in this type of local variable persists between function calls.

static

This value in a(n) __________ variable persists between function calls.

static local

An array of string objects that will hold 5 names would be declared using which statement?

string names [5];

By using the same ________ you can build relationships between data stored in two or more arrays.

subscript

To access an array element, use the array name and the element's

subscript

If you place a semicolon after the statement if (x < y)

the compiler will interpret the semicolon as a null statement

An array can store a group of values, but the values must be

the same data type

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

trailing else

Both of the following if statements perform the same operation. if (sales > 10000) commissionRate = 0.15; if (sales > 10000) commissionRate = 0.15;

true

What is the value of the following expression? true && true

true

A for statement contains three expressions: initialization, test, and:

update

_____________ represent storage locations in the computer's memory.

variables

Which of the following expressions will determine whether x is less than or equal to y? x > y x =< y x <= y x >= y

x <= y

When a relational expression is false, it has the value _________.

zero