Chapter 5 Computer Science Questions-AB

These are operators that add and subtract one from their operands.

++ and --

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 segment? n = 1; while (n <= 5) cout << n << ' '; n++;

1 1 1... and on forever

How many times will the following loop display "Hello"? for (int i = 1; i < 20; i++) cout << "Hello" << endl;

19

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 = 20; i > 0; i--) cout << "Hello" << endl;

20

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

Answer is NOT 0 1 2 possibly 3

True/ False: The condition that is tested by a while loop must be enclosed in parentheses and terminated with a semicolon.

False

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

False

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

The answer is NOT 20 probably 21

True/ False: A while loop's body can contain multiple statements, as long as they are enclosed in braces.

True

True/ False: It is possible to define a file stream object and open a file in one statement.

True

A loop that is inside another loop is called:

a nested loop

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

continue statement

To read data from a file, you define an object of this data type.

ifstream

This means to increase a value by one.

increment

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

initialization

This is a control structure that causes a statement or group of statements to repeat.

loop

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

opened

The do-while loop is a ________ loop that is ideal in situations where you always want the loop to iterate at least once.

post-test

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

post-test

When the increment operator precedes its operand, as in ++num1, the expression is in this mode.

prefix

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

update

You may define a ________ in the initialization expression of a for loop.

variable

What will the following code display? int number = 6; cout << number++ << endl;

6

What will the following code display? int number = 6; ++number; cout << number << endl;

7

What will the following code display? int number = 6; number++; cout << number << endl;

7

int number = 6; cout << ++number << endl;

7

True/ False: You may nest while and do-while loops, but you may not nest for loops.

False

True/ False: You may not use the break statement in a nested loop.

False

The statements in the body of a while loop may never be executed, whereas the statements in the body of a do-while loop will be executed:

at least once

This statement causes a loop to terminate early.

break

A file ________ is a small holding section of memory that file-bound information is first written to.

buffer

The while loop contains 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

This is a pre-test loop that is ideal in situations where you do not want the loop to iterate if the condition is false from the beginning.

while