Deck 5: Control Structures II (Repetition)

Question 1

The number of iterations of a counter-controlled loop is known in advance.

Answer 1

True

Question 2

Assume that all variables are properly declared.The following for loop executes 20 times.
for (i = 0; i <= 20; i++)
cout << i;

Answer 2

False

Question 3

What is the output of the following C++ code? num = 10;
While (num > 10)
Num = num - 2;
Cout << num << endl;

A) 0
B) 6
C) 8
D) 10

Answer 3

D

Question 4

Suppose sum and num are int variables,and the input is 18 25 61 6 -1.What is the output of the following code? sum = 0;
Cin >> num;
While (num != -1)
{
Sum = sum + num;
Cin >> num;
}
Cout << sum << endl;

A) 92
B) 109
C) 110
D) 119

Question 5

The following while loop terminates when j > 20.
j = 0;
while (j < 20)
j++;

Question 6

In a sentinel-controlled while loop,the body of the loop continues to execute until the EOF symbol is read.

Question 7

The control variable in a flag-controlled while loop is a bool variable.

Question 8

What is the output of the following C++ code? count = 1;
Num = 25;
While (count < 25)
{
Num = num - 1;
Count++;
}
Cout << count << " " << num << endl;

A) 24 0
B) 24 1
C) 25 0
D) 25 1

Question 9

A(n)____-controlled while loop uses a bool variable to control the loop.

A) counter
B) sentinel
C) flag
D) EOF

Question 10

Consider the following code. int limit;
Int reps = 0;
Cin >> limit;
While (reps < limit)
{
Cin >> entry;
Triple = entry * 3;
Cout << triple;
Reps++;
}
Cout << endl;
This code is an example of a(n)____ while loop.

A) flag-controlled
B) counter-controlled
C) EOF-controlled
D) sentinel-controlled

Question 11

What is the output of the following C++ code? num = 100;
While (num <= 150)
Num = num + 5;
Cout << num << endl;

A) 150
B) 155
C) 160
D) 165

Question 12

The statement in the body of a while loop acts as a decision maker.

Question 13

In ____ structures,the computer repeats particular statements a certain number of times depending on some condition(s).

A) looping
B) branching
C) selection
D) sequence

Question 14

In a counter-controlled while loop,the loop control variable must be initialized before the loop.

Question 15

In the case of the sentinel-controlled while loop,the first item is read before the while loop is entered.

Question 16

Which of the following statements generates a random number between 0 and 50?

A) srand(time(0));
Num = rand() % 50;
B) srand(time(10));
Num = rand()/50;
C) srand(time(0));
Num = rand()50;
D) srand(time(10));
Num = rand() % 50;

Question 17

Assume all variables are properly declared.The output of the following C++ code is 2 3 4 5.
n = 1;
while (n < 5)
{
n++;
cout << n << " ";
}

Question 18

The control statements in the for loop include the initial statement,loop condition,and update statement.

Question 19

Consider the following code.(Assume that all variables are properly declared.) cin >> ch;
While (cin)
{
Cout << ch;
Cin >> ch;
}
This code is an example of a(n)____ while loop.

A) sentinel-controlled
B) flag-controlled
C) EOF-controlled
D) counter-controlled

Question 20

A loop that continues to execute endlessly is called a(n)____ loop.

A) end
B) unhinged
C) infinite
D) definite

Question 21

The ____ statement can be used to eliminate the use of certain (flag)variables.

A) while
B) switch
C) break
D) if

Question 22

What is the value of x after the following statements execute? int x = 5;
Int y = 30;
Do
X = x * 2;
While (x < y);

A) 5
B) 10
C) 20
D) 40

Question 23

When a continue statement is executed in a ____,the update statement always executes.

A) while loop
B) for loop
C) switch structure
D) do...while loop

Question 24

Which of the following is a repetition structure in C++?

A) if
B) switch
C) while...do
D) do...while

Question 25

What is the next Fibonacci number in the following sequence? 1,1,2,3,5,8,13,21,...

A) 34
B) 43
C) 56
D) 273

Question 26

Which of the following loops does not have an entry condition?

A) EOF-controlled while loop
B) sentinel-controlled while loop
C) do...while loop
D) for loop

Question 27

Suppose sum,num,and j are int variables,and the input is 4 7 12 9 -1.What is the output of the following code? cin >> sum;
Cin >> num;
For (j = 1; j <= 3; j++)
{
Cin >> num;
Sum = sum + num;
}
Cout << sum << endl;

A) 24
B) 25
C) 41
D) 42

Question 28

To generate a random number,you can use the function rand of the header file ____________________.

Question 29

The function eof is a member of the data type ____________________.

Question 30

A for loop is typically called a counted or ____________________ for loop.

Question 31

____ loops are called posttest loops.

A) break
B) for
C) while
D) do...while

Question 32

Which of the following loops is guaranteed to execute at least once?

A) counter-controlled while loop
B) for loop
C) do...while loop
D) sentinel-controlled while loop

Question 33

A semicolon at the end of the for statement (just before the body of the loop)is a(n)____________________ error.

Question 34

The function srand takes as input a(n)____________________ int,which acts as the seed for the algorithm.

Question 35

Suppose j,sum,and num are int variables,and the input is 26 34 61 4 -1.What is the output of the code? sum = 0;
Cin >> num;
For (int j = 1; j <= 4; j++)
{
Sum = sum + num;
Cin >> num;
}
Cout << sum << endl;

A) 124
B) 125
C) 126
D) 127

Question 36

What is the initial statement in the following for loop? (Assume that all variables are properly declared.) int i;
For (i = 1; i < 20; i++)
Cout << "Hello World";
Cout << "!" << endl;

A) i = 1;
B) i < 20;
C) i++;
D) cout << "Hello World";

Question 37

What is the output of the following C++ code? int j;
For (j = 10; j <= 10; j++)
Cout << j << " ";
Cout << j << endl;

A) 10
B) 10 10
C) 10 11
D) 11 11

Question 38

What is the output of the following loop? count = 5;
Cout << 'St';
Do
{
Cout << 'o';
Count--;
}
While (count <= 5);

A) St
B) Sto
C) Stop
D) This is an infinite loop.

Question 39

What executes immediately after a continue statement in a while and do-while loop?

A) loop-continue test
B) update statement
C) loop condition
D) the body of the loop

Question 40

Which executes first in a do...while loop?

A) the statement
B) loop condition
C) the expression
D) update statement

Question 41

In a while and for loop,the loop condition is evaluated before executing the body of the loop.Therefore,while and for loops are called ____________________ loops.

Question 42

In a(n)"____________________" problem,either the loop executes one too many or one too few times.

Question 43

The for loop body executes indefinitely if the loop condition is always ____________________.

Question 44

Putting one control structure statement inside another is called ____________________.

Question 45

A loop ____________________ is a set of statements that remains true each time the loop body is executed.

Question 46

The ____________________ loop has an exit condition but no entry condition.

Question 47

If a(n)____________________ statement is placed in a do...while structure,the loop-continue test is evaluated immediately after this statement.

Question 48

A software ____________________ is a piece of code written on top of an existing piece of code intended to fix a bug in the original code.

Question 49

The ____________________ statement is typically used for two purposes:
• To exit early from a loop.
• To skip the remainder of a switch structure.

Question 50

A do...while loop is a(n)____________________ loop,since the loop condition is evaluated after executing the body of the loop.