Chapter 03

Question 1

1. Assume that the following variables are defined:
   int age;
   double pay;
   char section;
   Write a single cin statement that will read input into each of these variables.

Answer 1

1.

cin»_space; age»_space; pay»_space; section;

Question 2

2. Assume a string object has been defined as follows:
   string description;
   A) Write a cin statement that reads in a one-word string.
   B) Write a statement that reads in a string that can contain multiple words separated
   by blanks.

Answer 2

A)
cin»_space; description;

B)
getline (cin,description);

Question 3

3. What header files must be included in the following program?
int main()
{
double amount = 89.7;
cout << showpoint << fixed;
cout << setw(8) << amount << endl;
return 0;
}

Answer 3

#include 
#include

Question 4

28 / 4 - 2
6 + 12 * 2 - 8
4 + 8 * 2
6 + 17 % 3 - 2
2 + 22 * (9 - 7)
(8 + 7) * 2
(16 + 7) % 2 - 1
12 / (10 - 6)
(19 - 3) * (2 + 2) / 4

Answer 4

5
22
20
6
46
30
0
3
16

Question 5

6. Assume a program has the following variable definitions:
   int units;
   float mass;
   double weight;
   and the following statement:
   weight = mass * units;
   Which automatic data type conversion will take place?
   A) mass is demoted to an int, units remains an int, and the result of mass * units is
   an int.
   B) units is promoted to a float, mass remains a float, and the result of mass *
   units is a float.
   C) units is promoted to a float, mass remains a float, and the result of mass *
   units is a double.

Answer 5

c

Question 6

7. Assume a program has the following variable de nitions:
int a, b = 2;
float c = 4.2;
and the following statement:
a = b * c;
What value will be stored in a?
A) 8.4
B) 8
C) 0
D) None of the above

Answer 6

b

Question 7

8. Assume that qty and salesReps are both integers. Use a type cast expression to
   rewrite the following statement so it will no longer perform integer division.
   unitsEach = qty / salesReps;

Answer 7

unitsEach = static_cast(qty)/salesReps;

Question 8

9. Rewrite the following variable definition so the variable is a named constant.
   int rate;

Answer 8

9.

const int RATE = 12;

Question 9

10 Complete the following table by writing statements with combined assignment operators
in the right-hand column. The statements should be equivalent to the statements
in the left-hand column.

x = x + 5;
total = total + subtotal;
dist = dist / rep;
ppl = ppl * period;
inv = inv - shrinkage;
num = num % 2;

Answer 9

x +=5;
total +=subtotal;
dist/=rep;
ppl*=period;
inv-=shrinkage;
num%=2

Question 10

11. Write a multiple assignment statement that can be used instead of the following group
of assignment statements:
east = 1;
west = 1;
north = 1;
south = 1;

Answer 10

east = west = north = south = 1;

Question 11

12. Write a cout statement so the variable divSales is displayed in a field of 8 spaces, in
    fixed point notation, with a precision of 2 decimal places. The decimal point should
    always be displayed.

Answer 11

cout

Question 12

13. Write a cout statement so the variable totalAge is displayed in a field of 12 spaces,
    in fixed point notation, with a precision of 4 decimal places.

Answer 12

13.
cout «_space;setw(12) «_space;fixed
«_space;setprecision(4) «_space;totalAge;

Question 13

14. Write a cout statement so the variable population is displayed in a field of 12
    spaces, left-justified, with a precision of 8 decimal places. The decimal point should
    always be displayed.

Answer 13

cout

Question 14

15. The __________ library function returns the cosine of an angle.

Answer 14

cos

Question 15

16. The __________ library function returns the sine of an angle.

Answer 15

sin

Question 16

17. The __________ library function returns the tangent of an angle.

Answer 16

tan

Question 17

18. The __________ library function returns the exponential function of a number.

Answer 17

exp

Question 18

19. The __________ library function returns the remainder of a floating point division.

Answer 18

fmod

Question 19

20. The __________ library function returns the natural logarithm of a number.

Answer 19

log

Question 20

21. The __________ library function returns the base-10 logarithm of a number.

Answer 20

log10

Question 21

22. The __________ library function returns the value of a number raised to a power.

Answer 21

pow

Question 22

23. The __________ library function returns the square root of a number.

Answer 22

sqrt

Question 23

24. The __________ file must be included in a program that uses the mathematical functions.

Answer 23

include