Chapter 5: Checkpoints, CSCI Ch 5 (iteration), Hogan Chapter 5

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38) 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

D

12) 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

D

28) 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

D

39) To write data to a file, you define an object of this data type. A) outputFile B) ifstream C) fstream D) ofstream

D

3) True/False: A while loop is somewhat limited, because the counter can only be incremented by one each time through the loop.

FALSE

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

FALSE

7) True/False: You may not use the break and continue statements within the same set of nested loops.

FALSE

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

FALSE

10) True/False: Multiple relational expressions cannot be placed into the test condition of a for loop.

TRUE

13) True/False: An output file is a file that data is written to.

TRUE

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

TRUE

15) True/False: In C++ 11 you can pass a string object as argument to a file stream object's open member function.

TRUE

16) True/False: string objects have a member function named c_str that returns the contents of the object formatted as a null-terminated C-string.

TRUE

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

TRUE

4) True/False: An initialization expression may be omitted from the for loop if no initialization is required.

TRUE

6) True/False: If you want to stop a loop before it goes through all its iterations, the break statement may be used.

TRUE

9) True/False: The update expression of a for loop can contain more than one statement, e.g. counter++, total+= sales.

TRUE

This statement causes a loop to terminate early. stop break null terminate

break

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

continue

This is a variable that is regularly incremented or decremented each time a loop iterates. constant counter control statement null terminator

counter

Something within a while loop must eventually cause the condition to become false, or a(n) __________ results. null value infinite loop unexpected exit compiler error

infinite loop

This is a control structure that causes a statement or group of statements to repeat. decision statement constant loop cout object

loop

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 pre-test infinite null-terminated

post-test

The do-while loop is considered a(n) _________ loop. pre-test post-test infinite limited

post-test

The while loop is this type of loop? post-test pre-test infinite limited

pre-test

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

prefix

When used as part of an expression and/or in an assignment operation this operator increments the value of its operand before the operand is used in the expression, or assignment operation. prefix increment postfix increment prefix decrement postfix decrement

prefix increment

16) Look at the following statement. while (x++ < 10) Which operator is used first? A) ++ B) < C) Neither. The expression is invalid.

B

41) 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;

C

21) 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

D

1) True/False: The increment and decrement operators can be used in mathematical expressions; however, they cannot be used in relational expressions.

FALSE

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

FALSE

x = 0; if (++x) cout << "It is true! \n"; else cout << "It is false! \n";

It is true!

x = 99; if (x++ < 100) cout "It is true! \n"; else cout << "It is false! \n";

It is true!

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 a statement or block that is repeated only if the expression is false one line of code that is repeated once, if the expression is true a statement or block that is repeated once, if the expression is true

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

If you want a user to enter exactly 20 values, which loop would be the best to use? do-while for while infinite

for

If you place a semicolon after the test expression in a while loop, it is assumed to be a(n): pre-test loop post-test loop null statement infinite loop

null statement

These are operators that add and subtract one from their operands. plus and minus ++ and -- binary and unary conditional and relational

++ and --

How many lines will the following while loop display? int count = 1; while (count < 5) count << " My favorite day is Sunday \n"; count = count + 1;

0 lines - more than one statement, no curly braces. This means the line that increments count is not in the loop, so count always remains less than 5, causing an infinite loop. The cout statement executes over and over again until the user stops the program.

How many lines will the following while loop display? int count = 1; while (count < 5); { cout << "My favorite days is Sunday \n"; count = count + 1;

0 lines - semicolon after test expression. This causes an infinite loop that prints nothing.

How many lines will the following while loop display? int count = 10 while (count < 5) { cout << "My favorite day is Sunday \n"; count = count + 1 }

0 lines - the test condition of the line is initially false, so the body of the loop is never executed.

What is the output of the following code segment? n = 1; for ( ; n <= 5; ) cout << n << " "; n++; 1 2 3 4 5 1 1 1 ... and on forever 2 3 4 5 6 1 2 3 4 2 3 4 5

1 1 1 ... and on forever

What is the output of the following code segment? n = 1; while (n <= 5) cout << n << ' '; n++; 1 2 3 4 5 1 1 1... and on forever 2 3 4 5 6 1 2 3 4 5 2 3 4 5

1 1 1... and on forever

3) 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

A

32) What will the following code display? int number = 6; cout << number++ << endl; A) 6 B) 5 C) 7 D) 0

A

34) 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

A

4) 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

A

7) 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

A

8) A for statement contains three expressions: initialization, test, and A) update B) reversal C) null D) validation E) None of these

A

5) The while loop is this type of loop. A) post-test B) pre-test C) infinite D) limited E) None of these

B

14) This means to increase a value by one. A) decrement B) increment C) modulus D) parse E) None of these

B

23) The do-while loop is considered a(n) ________ loop. A) pre-test B) post-test C) infinite D) limited E) None of these

B

26) This statement causes a loop to terminate early. A) stop B) break C) null D) terminate E) None of these

B

27) 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

B

29) 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.

B

35) 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

B

43) 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

B

47) 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

C

10) 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

C

17) 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

C

24) 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

C

30) What will the following code display? int number = 6; number++; cout << number << endl; A) 6 B) 5 C) 7 D) 0

C

31) What will the following code display? int number = 6; ++number; cout << number << endl; A) 6 B) 5 C) 7 D) 0

C

33) What will the following code display? int number = 6; cout << ++number << endl; A) 6 B) 5 C) 7 D) 0

C

37) 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

C

6) 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

C

9) In a for statement, this expression is executed only once. A) test B) null C) initialization D) validation E) None of these

C

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

FALSE

What will the following program segment display? x = 2; y = x++; cout << x << " " << y;

2

What will display when the following lines of code are executed? int count = 1 while (count < 10) { cout << count << " "; count = count + 2; }

1 3 5 7 9

13) 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

D

You may define a __________ in the initialization expression of a for loop. constant function variable new data type

variable

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. do-while while for infinite

while

Look at the following statement. while (x++ < 10) Which operator is used first? ++ < Neither. The expression is invalid. No answer text provided.

<

45) 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

A

1) 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

B

A loop that is inside another loop is called: an infinite loop a pre-test loop a post-test loop a nested loop

a nested loop

A for statement contains three expressions: initialization, test, and update reversal null validation

update

25) 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

B

This means to increase a value by one. decrement increment modulus parse

increment

How many lines will the following while loop display? int count = 1; while (count < 5) { count << "My favorite day is Sunday \n"; count = count + 1; }

4 lines

11) The do-while loop is a(n) ________ 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

A

48) 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

A

15) 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

B

18) 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

B

19) 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

B

2) 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

B

20) 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

B

22) 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

B

40) To read data from a file, you define an object of this data type. A) inputFile B) ifstream C) fstream D) ofstream

B

46) 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

B

36) To allow file access in a program, you must #include this header file. A) file B) fileaccess C) fstream D) cfile

C

42) 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

C

44) 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

D

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

for

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 false is true does not evaluate to true or false evaluates to true or false

is true

This is a special value that marks the end of a list of values. constant variable loop sentinel

sentinel


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