Deck 5: Loops and Files

Question 1

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

A) update
B) reversal
C) null
D) validation
E) None of these

Answer 1

A

Question 2

The while loop is this type of loop.

A) post-test
B) pre-test
C) infinite
D) limited
E) None of these

Answer 2

B

Question 3

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

A) post-test
B) pre-test
C) infinite
D) null-terminated
E) None of these

Answer 3

A

Question 4

Something within a while loop must eventually cause the condition to become false, or a(n) __________ results.

A) null value
B) infinite loop
C) unexpected exit
D) compiler error
E) None of these

Question 5

What is the output of the following code segment? n = 1;
While (n <= 5)
Cout << n << ' ';
N++;

A) 1 2 3 4 5
B) 1 1 1... and on forever
C) 2 3 4 5 6
D) 1 2 3 4
E) 2 3 4 5

Question 6

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:

A) at least once
B) at least twice
C) as many times as the user wishes
D) never
E) None of these

Question 7

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

A) ++
B) <
C) Neither. The expression is invalid.

Question 8

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

A) test
B) null
C) initialization
D) validation
E) None of these

Question 9

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

A) decision statement
B) constant
C) loop
D) cout object
E) None of these

Question 10

If you place a semicolon after the test expression in a while loop, it is assumed to be a(n):

A) pre-test loop
B) post-test loop
C) null statement
D) infinite loop
E) None of these

Question 11

This operator increments the value of its operand, then uses the value in context.

A) prefix increment
B) postfix increment
C) prefix decrement
D) postfix decrement
E) None of these

Question 12

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

A) break
B) terminate
C) re-iterate
D) continue
E) None of these

Question 13

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

A) a statement or block that is repeated as long as the expression is true
B) a statement or block that is repeated only if the expression is false
C) one line of code that is repeated once, if the expression is true
D) a statement or block that is repeated once, if the expression is true

Question 14

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

A) is false
B) is true
C) does not evaluate to true or false
D) evaluates to true or false
E) None of these

Question 15

This means to increase a value by one.

A) decrement
B) increment
C) modulus
D) parse
E) None of these

Question 16

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

A) postfix
B) prefix
C) preliminary
D) binary
E) None of these

Question 17

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

A) constant
B) function
C) variable
D) new data type
E) None of these

Question 18

This is a variable that is regularly incremented or decremented each time a loop iterates.

A) constant
B) counter
C) control statement
D) null terminator
E) None of these

Question 19

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

A) plus and minus
B) ++ and --
C) binary and unary
D) conditional and relational
E) None of these

Question 20

A loop that is inside another loop is called:

A) an infinite loop
B) a pre-test loop
C) a post-test loop
D) a nested loop
E) None of these

Question 21

What is the output of the following code segment? n = 1;
For ( ; n <= 5; )
Cout << n << ' ';
N++;

A) 1 2 3 4 5
B) 1 1 1 ... and on forever
C) 2 3 4 5 6
D) 1 2 3 4
E) 2 3 4 5

Question 22

What will the following code display? int number = 6;
Int x = 0;
X = number--;
Cout << x << endl;

A) 6
B) 5
C) 7
D) 0

Question 23

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

A) inputFile
B) ifstream
C) fstream
D) ofstream

Question 24

This is a special value that marks the end of a list of values.

A) constant
B) variable
C) loop
D) sentinel
E) None of these

Question 25

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

A) 6
B) 5
C) 7
D) 0

Question 26

This statement causes a loop to terminate early.

A) stop
B) break
C) null
D) terminate
E) None of these

Question 27

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

A) 6
B) 5
C) 7
D) 0

Question 28

To write data to a file, you define an object of this data type.

A) outputFile
B) ifstream
C) fstream
D) ofstream

Question 29

What will the following code display? int number = 6
Int x = 0;
X = --number;
Cout << x << endl;

A) 6
B) 5
C) 7
D) 0

Question 30

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

A) do-while
B) while
C) for
D) infinite
E) None of these

Question 31

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

A) 6
B) 5
C) 7
D) 0

Question 32

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

A) 6
B) 5
C) 7
D) 0

Question 33

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

A) pre-test
B) post-test
C) infinite
D) limited
E) None of these

Question 34

To allow file access in a program, you must #include this header file.

A) file
B) fileaccess
C) fstream
D) cfile

Question 35

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

A) break
B) terminate
C) return
D) continue
E) None of these

Question 36

This may be used to write information to a file.

A) cout object
B) pen object
C) output object
D) stream insertion operator
E) None of these

Question 37

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

A) 0
1
2
3
4
5
B) 0
1
2
3
4
C) 01 2 3 4
D) The loop will display numbers starting at 0, for infinity.

Question 38

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.

A) do-while
B) while
C) for
D) infinite
E) None of these

Question 39

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

A) name
B) number
C) buffer
D) segment
E) None of these

Question 40

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

A) do-while
B) for
C) while
D) infinite
E) None of these

Question 41

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

A) 20
B) 19
C) 21
D) An infinite number of times

Question 42

A while loop is somewhat limited, because the counter can only be incremented by one each time through the loop.

Question 43

Assuming dataFile is a file stream object, the statement dataFile.close();

A) is illegal in C++
B) needs a filename argument to execute correctly
C) closes a file
D) is legal but risks losing valuable data
E) None of these

Question 44

If you want to stop a loop before it goes through all its iterations, the break statement may be used.

Question 45

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

Question 46

You may not use the break statement in a nested loop.

Question 47

The update expression of a for loop can contain more than one statement,
e.g. counter++, total+= sales.

Question 48

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

A) 20
B) 19
C) 21
D) An infinite number of times

Question 49

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

A) closed
B) opened
C) buffered
D) initialized
E) None of these

Question 50

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

Question 51

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

Question 52

An initialization expression may be omitted from the for loop if no initialization is required.

Question 53

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

A) 20
B) 19
C) 21
D) An infinite number of times

Question 54

What will the following code display? int x = 0;
For (int count = 0; count < 3; count++)
X += count;
Cout << x << endl;

A) 0
1
2
B) 0
C) 6
D) 3

Question 55

Multiple relational expressions cannot be placed into the test condition of a for loop.

Question 56

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

Question 57

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?

A) write(outFile, number);
B) outFile >> number;
C) outFile << number;
D) number >> outFile;

Question 58

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

Question 59

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

A) 20
B) 19
C) 21
D) An infinite number of times

Question 60

The increment and decrement operators can be used in mathematical expressions; however, they cannot be used in relational expressions.

Question 61

It is possible to define a file stream object and open a file in one statement.

Question 62

An output file is a file that data is written to.