C++ solutions for : [Object-Oriented Programming in C++, Third Edition]

CHAPTER 2C++ PROGRAMMING BASICS

Questions:
----
1. Dividing a program into functions
a. is the key to Object-Oriented Programming.
b. makes the program easier to conceptualize.
c. may reduce the size of the program.
d. makes the program run faster.
2. A function name must be followed by ________.
3. A function body is delimited by ________.
4. Why is the main() function special?
5. A C++ instruction that tells the computer to do something is called a ________.
6. Write an example of a normal C++ comment and an example of an old-fashioned /* comment.
7. An expression
a. usually evaluates to a numerical value.
b. indicates the emotional state of the program.
c. always occurs outside a function.
d. may be part of a statement.
8. Specify how many bytes are occupied by the following data types in a 32-bit system:
a. Type int
b. Type long double
c. Type float
d. Type long
9. True or false: A variable of type char can hold the value 301.
10. What kind of program elements are the following?
a. 12
b. a
c. 4.28915
d. JungleJim
e. JungleJim()
11. Write statements that display on the screen
a. the character x.
b. the name Jim.
c. the number 509.
12. True or false: In an assignment statement, the value on the left of the equal sign is always equal to the value on the right.
13. Write a statement that displays the variable george in a field 10 characters wide.
14. What header file must you #include with your source file to use cout and cin?
15. Write a statement that gets a numerical value from the keyboard and places it in the variable temp.
16. What header file must you perform #include with your program to use setw?
17. Two exceptions to the rule that the compiler ignores whitespace are ________ and ________.
18. True or false: Its perfectly all right to use variables of different data types in the same arithmetic expression.
19. The expression 11%3 evaluates to ________.
20. An arithmetic assignment operator combines the effect of what two operators?
21. Write a statement that uses an arithmetic assignment operator to increase the value of the variable temp by 23. Write the same statement without the arithmetic assignment operator.
22. The increment operator increases the value of a variable by how much?
23. Assuming var1 starts with the value 20, what will the following code fragment print out?
cout << var1--;
cout << ++var1;
24. In the examples weve seen so far, header files have been used for what purpose?
25. The actual code for library functions is contained in a ________ file.
__________

My answers:
----
1. makes the program easier to conceptualize, makes the program run faster.
2. '()'.
3. '{' and '}'.
4. The programme start from it.
5. an order, an event.
6. //Normal C++ comment, /*old-fashioned comment*/.
7. may be part of a statement.
8. Type int, Type long.
9. False.
10. 12 --> int,
'a' --> char,
4.28915 --> float,
JungleJim --> variable name,
JungleJim() --> function name.
11. #cout<<"x"; //or cout<<'x';
#cout<<"Jim";
#cout<<509;
12. False;
13. cout<<setw(10)<<george;
14. iostream.
15. cin >>temp;
16. iomanip.
17. between statments, end lines.
18. True.
19. 2.
20. assign, operation.
21. temp += 23;
temp = temp + 23;
22. 1
23. 20
21
24. to be able to use cout function.
25. lib.
___________

Answers:
---
1. b, c
2. parentheses
3. braces { }
4. Its the first function executed when the program starts
5. statement
6.
// this is a comment
/* this is a comment */

7. a, d
8. a. 4
b. 10
c. 4
d. 4
9. False
10. a. integer constant
b. character constant
c. floating-point constant
d. variable name or identifier
e. function name
11. a. cout << x;
b. cout << Jim;
c. cout << 509;
12. False; theyre not equal until the statement is executed.
13. cout << setw(10) << george;
14. IOSTREAM
15. cin >> temp;
16. IOMANIP
17. string constants, preprocessor directives
18. true
19. 2
20. assignment (=) and arithmetic (like + and *)
21.
temp += 23;
temp = temp + 23;

22. 1
23. 2020
24. to provide declarations and other data for library functions, overloaded operators, and objects
25. library
________

/*7. You can convert temperature from degrees Celsius to degrees Fahrenheit by multiplying by 9/5
and adding 32. Write a program that allows the user to enter a floating-point number representing
degrees Celsius, and then displays the corresponding degrees Fahrenheit.*/
#include<iostream.h>
#include<conio.h>

void main(void)
{
cout<<"### Programmed By Amahdy(MrJava) ,right restricted.~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n";
cout<<"------------------------\n\n";
float c_temp;

do{
cout<<"Enter the degrees Celsius\t\t\t\xdb ";
cin >>c_temp;
cout<<"The corresponding degrees Fahrenheit is :\t\xdb "<<((9/5)*c_temp)+32<<endl;
cout<<"\n !Press c to continue or any key to exit."<<endl<<endl;
}while(getch()=='c');
}

/*8. When a value is smaller than a field specified with setw(), the unused locations are, by default,
filled in with spaces. The manipulator setfill() takes a single character as an argument and causes this
character to be substituted for spaces in the empty parts of a field. Rewrite the WIDTH program so
that the characters on each line between the location name and the population number are filled in
with periods instead of spaces, as in

Portcity....2425785
*/
#include<iostream.h>
#include<conio.h>
#include<iomanip.h>
//WIDTH program:
/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
!// width2.cpp
!// demonstrates setw manipulator
!#include <iostream>
!#include <iomanip> // for setw
!using namespace std;
!
!int main()
! {
! long pop1=2425785, pop2=47, pop3=9761;
!
! cout << setw(8) << "LOCATION" << setw(12)
! << "POPULATION" << endl
! << setw(8) << "Portcity" << setw(12) << pop1 << endl
! << setw(8) << "Hightown" << setw(12) << pop2 << endl
! << setw(8) << "Lowville" << setw(12) << pop3 << endl;
! return 0;
! }
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
void main(void)
{
cout<<"### Programmed By Amahdy(MrJava) ,right restricted.~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n";
cout<<"------------------------\n\n";
long pop1=2425785, pop2=47, pop3=9761;

do{
cout << setw(8) << "LOCATION" << setw(12)
<< "POPULATION" << endl
<< setw(8) << "Portcity" << setw(12) << setfill('.') << pop1 << endl
<< setw(8) << "Hightown" << setw(12) << setfill('.') << pop2 << endl
<< setw(8) << "Lowville" << setw(12) << setfill('.') << pop3 << endl;
cout<<"\n !Press c to continue or any key to exit."<<endl<<endl;
}while(getch()=='c');
}

/*9. If you have two fractions, a/b and c/d, their sum can be obtained from the formula

a c a*d + b*c
-- + -- = ----
b d b*d

For example, 1/4 plus 2/3 is
1 2 1*3 + 4*2 3 + 8 11
-- + -- = ---- = --- = --
4 3 4*3 12 12

Write a program that encourages the user to enter two fractions, and then displays their sum in
fractional form. (You dont need to reduce it to lowest terms.) The interaction with the user might
look like this:

Enter first fraction: 1/2
Enter second fraction: 2/5
Sum = 9/10

You can take advantage of the fact that the extraction operator (>>) can be chained to read in more
than one quantity at once:

cin >> a >> dummychar >> b;
*/
#include<iostream.h>
#include<conio.h>

void main(void)
{
cout<<"### Programmed By Amahdy(MrJava) ,right restricted.~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n";
cout<<"------------------------\n\n";
int first[2], last[2];
char operation; //In this sample programme not needed but generally for error detection only!

do{
cout<<"Enter first fraction: ";
cin >>first[0]>>operation>>last[0]; //if (operation != '/') {raise error event}
cout<<"Enter second fraction: ";
cin >>first[1]>>operation>>last[1]; //if (operation != '/') {raise error event}
cout<<"Sum = "<<(first[0]*last[1] + last[0]*first[1])<<operation<<(last[0]*last[1])<<endl;
cout<<"\n !Press c to continue or any key to exit."<<endl<<endl;
}while(getch()=='c');
}

CHAPTER 3LOOPS AND DECISIONS

Questions:
----
1. A relational operator
a. assigns one operand to another.
b. yields a Boolean result.
c. compares two operands.
d. logically combines two operands.
2. Write an expression that uses a relational operator to return true if the variable george is not equal to sally.
3. Is 1 true or false?
4. Name and describe the usual purpose of three expressions in a for statement.
5. In a for loop with a multistatement loop body, semicolons should appear following
a. the for statement itself.
b. the closing brace in a multistatement loop body.
c. each statement within the loop body.
d. the test expression.
6. True or false: The increment expression in a for loop can decrement the loop variable.
7. Write a for loop that displays the numbers from 100 to 110.
8. A block of code is delimited by _________.
9. A variable defined within a block is visible
a. from the point of definition onward in the program.
b. from the point of definition onward in the function.
c. from the point of definition onward in the block.
d. throughout the function.
10. Write a while loop that displays the numbers from 100 to 110.
11. True or false: Relational operators have a higher precedence than arithmetic operators.
12. How many times is the loop body executed in a do loop?
13. Write a do loop that displays the numbers from 100 to 110.
14. Write an if statement that prints Yes if a variable age is greater than 21.
15. The library function exit() causes an exit from
a. the loop in which it occurs.
b. the block in which it occurs.
c. the function in which it occurs.
d. the program in which it occurs.
16. Write an if...else statement that displays Yes if a variable age is greater than 21, and displays No otherwise.
17. The getche() library function
a. returns a character when any key is pressed.
b. returns a character when [Enter] is pressed.
c. displays a character on the screen when any key is pressed.
d. does not display a character on the screen.
18. What is the character obtained from cin when the user presses the [Enter] key?
19. An else always matches the _________ if, unless the if is _________.
20. The else...if construction is obtained from a nested if...else by ________________.
21. Write a switch statement that prints Yes if a variable ch is y, prints No if ch is n, and prints Unknown response otherwise.
22. Write a statement that uses a conditional operator to set ticket to 1 if speed is greater than 55, and to 0 otherwise.
23. The && and || operators
a. compare two numeric values.
b. combine two numeric values.
c. compare two Boolean values.
d. combine two Boolean values.
24. Write an expression involving a logical operator that is true if limit is 55 and speed is greater than 55.
25. Arrange in order of precedence (highest first) the following kinds of operators: logical, unary, arithmetic, assignment, relational, conditional.
26. The break statement causes an exit
a. only from the innermost loop.
b. only from the innermost switch.
c. from all loops and switches.
d. from the innermost loop or switch.
27. Executing the continue operator from within a loop causes control to go to ________.
28. The goto statement causes control to go to
a. an operator.
b. a label.
c. a variable.
d. a function.
__________

My answers:
----
1. yields a Boolean result, compares two operands.
2. if(george != sally) op=true.
3. true.
4. definitions of some variavles, compare of operands to hold the exit for condition, the changes in variables in each loop.
5. each statement within the loop body, the test expression.
6. true.
7. for(int i=100; i<111; i++) cout<<i<<endl;
8. {}
9. from the point of definition onward in the function.
10. int i=110; while(i<111) cout<<i++<<endl;
11. false.
12. one time.
13. int i=110; do cout<<i++<<endl; while(i<111);
14. if(age>21) cout<<"Yes";
15. the program in which it occurs.
16. if(age>21) cout<<"Yes"; else cout<<"No";
17. returns a character when any key is pressed, displays a character on the screen when any key is pressed.
18. '\r'
19. opposit of the, done.
20. nested if contidtions.
21. switch(ch){case 'y': cout<<"Yes"; break; case 'n': cout<<"No"; break; default: cout<<"Unknown response";}
22. ticket = (speed>55) ? 1 : false;
23. combine two Boolean values.
24. if(limit == 55 && speed > 55) op = true;
25. ?.
26. from the innermost loop or switch.
27. begin of loop.
28. a label.
___________

Answers:
---
1. b, c
2. george != sally
3. 1 is true; only 0 is false.
4. The initialize expression initializes the loop variable, the test expression tests the loop variable, and the increment expression changes the loop variable.
5. c, d
6. True
7.
for(int j=100; j<=110; j++)
cout << endl << j;

8. braces (curly brackets)
9. c
10.
int j = 100;
while( j <= 110 )
cout << endl << j++;

11. False
12. At least once.
13.
int j = 100;
do
cout << endl << j++;
while( j <= 110 );

14.
if(age > 21)
cout << Yes;

15. d
16.
if( age > 21 )
cout << Yes;
else
cout << No;

17. a, c
18. \r
19. preceding, surrounded by braces
20. reformatting
21.
switch(ch)
{
case y:
cout << Yes;
break;
case n:
cout << No;
break;
default:
cout << Unknown response;
}

22. ticket = (speed > 55) ? 1 : 0;
23. d
24. limit == 55 && speed > 55
25. unary, arithmetic, relational, logical, conditional, assignment
26. d
27. the top of the loop
28. b
________

/*6. Modify the FACTOR program in this chapter so that it repeatedly asks for a number and
calculates its factorial, until the user enters 0, at which point it terminates. You can enclose the
relevant statements in FACTOR in a while loop or a do loop to achieve this effect.*/
#include<iostream>
using namespace std;
#include<conio.h>

// The FACTOR program:
/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
!#include <iostream>
!using namespace std;
!
!int main()
! {
! unsigned int numb;
! unsigned long fact=1; //long for larger numbers
!
! cout << Enter a number: ;
! cin >> numb; //get number
!
! for(int j=numb; j>0; j--) //multiply 1 by
! fact *= j; //numb, numb-1, ..., 2, 1
! cout << Factorial is << fact << endl;
! return 0;
! }
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/

void main(void)
{
cout<<"### Programmed By Amahdy(MrJava) ,right restricted.~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n";
cout<<"------------------------\n"<<endl;

unsigned int numb, i;
unsigned long fact;

cout<<"Enter a number: ";
cin >>numb;
do{
fact=1; i=0;
for(i=numb; i>0; i--) fact *= i;
cout<<"\n\nFactorial is "<<fact<<endl;
cout<<" !Enter 0 to exit or any other number to calculate it's factorial: ";
cin >>numb;
}while(numb!=0);
}

/*7. Write a program that calculates how much money youll end up with if you invest an amount of
money at a fixed interest rate, compounded yearly. Have the user furnish the initial amount, the
number of years, and the yearly interest rate in percent. Some interaction with the program might
look like this:

Enter initial amount: 3000
Enter number of years: 10
Enter interest rate (percent per year): 5.5
At the end of 10 years, you will have 5124.43 dollars.

At the end of the first year you have 3000 + (3000 * 0.055), which is 3165. At the end of the
second year you have 3165 + (3165 * 0.055), which is 3339.08. Do this as many times as there
are years. A for loop makes the calculation easy.*/
#include<iostream.h>
#include<conio.h>

void main(void)
{
cout<<"### Programmed By Amahdy(MrJava) ,right restricted.~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n";
cout<<"------------------------\n"<<endl;

int num_year; float init_amount, intrst_rate;

do{
cout<<"Enter initial amount : "; cin >>init_amount;
cout<<"Enter number of years : "; cin >>num_year ;
cout<<"Enter interest rate (percent per year): "; cin >>intrst_rate;
for(int i=0; i<num_year; i++) init_amount += init_amount*intrst_rate/100;
cout<<"At the end of "<<num_year
<<" years, you will have "<<init_amount
<<" dollars.";
cout<<"\n\n !Press c to continue or any key to exit."<<endl<<endl;
}while(getch()=='c');
}

/*8. Write a program that repeatedly asks the user to enter two money amounts expressed in old-
style British currency: pounds, shillings, and pence. (See Exercises 10 and 12 in Chapter 2, ++
Programming Basics.) The program should then add the two amounts and display the answer,
again in pounds, shillings, and pence. Use a do loop that asks the user if the program should be
terminated. Typical interaction might be

Enter first amount: 5.10.6
Enter second amount: 3.2.6
Total is 8.13.0
Do you wish to continue (y/n)?

To add the two amounts, youll need to carry 1 shilling when the pence value is greater than 11, and
carry 1 pound when there are more than 19 shillings.*/
#include<iostream.h>
#include<conio.h>

void main(void)
{
cout<<"### Programmed By Amahdy(MrJava) ,right restricted.~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n";
cout<<"------------------------\n"<<endl;

int m[2][3]; char sep; //m (money), sep (char_separator).

do{
cout<<"Enter first amount : \x9c";
cin >>m[0][0]>>sep>>m[0][1]>>sep>>m[0][2];
cout<<"Enter second amount: \x9c";
cin >>m[1][0]>>sep>>m[1][1]>>sep>>m[1][2];
m[0][0] += m[1][0]; m[0][1] += m[1][1]; m[0][2] += m[1][2];
if(m[0][2]>11){m[0][1] += static_cast<int>(m[0][2]/12); m[0][2] %= 12;}
if(m[0][1]>19){m[0][0] += static_cast<int>(m[0][1]/20); m[0][1] %= 20;}
cout<<"Total is : \x9c"<<m[0][0]<<sep<<m[0][1]<<sep<<m[0][2];
cout<<"\n\n !Press c to continue or any key to exit."<<endl<<endl;
}while(getch()=='c');
}

/*9. Suppose you give a dinner party for six guests, but your table seats only four. In how many ways
can four of the six guests arrange themselves at the table? Any of the six guests can sit in the first
chair. Any of the remaining five can sit in the second chair. Any of the remaining four can sit in the
third chair, and any of the remaining three can sit in the fourth chair. (The last two will have to
stand.) So the number of possible arrangements of six guests in four chairs is 6*5*4*3, which is
360. Write a program that calculates the number of possible arrangements for any number of guests
and any number of chairs. (Assume there will never be fewer guests than chairs.) Dont let this get
too complicated. A simple for loop should do it.*/
#include<iostream.h>
#include<conio.h>

void main(void)
{
cout<<"### Programmed By Amahdy(MrJava) ,right restricted.~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n";
cout<<"------------------------\n"<<endl;

int ch_num, gs_num, result;

do{
cout<<"Enter number of guests : \xdb "; cin >>gs_num;
cout<<"Enter number of chairs : \xdb "; cin >>ch_num;
result=1; for(int i=0; i<ch_num; i++) result*=(gs_num-i);
cout<<"The number of possible arrangements is : \xdb "<<result;
cout<<"\n\n !Press c to continue or any key to exit."<<endl<<endl;
}while(getch()=='c');
}

/*10. Write another version of the program from Exercise 7 so that, instead of finding the final
amount of your investment, you tell the program the final amount and it figures out how many years it
will take, at a fixed rate of interest compounded yearly, to reach this amount. What sort of loop is
appropriate for this problem? (Dont worry about fractional years; use an integer value for the year.)*/
#include<iostream.h>
#include<conio.h>

//Old programme:
/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~
#include<iostream.h>
#include<conio.h>

void main(void)
{
cout<<"### Programmed By Amahdy(MrJava) ,right restricted.~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n";
cout<<"------------------------\n"<<endl;

int num_year; float init_amount, intrst_rate;

do{
cout<<"Enter initial amount : "; cin >>init_amount;
cout<<"Enter number of years : "; cin >>num_year ;
cout<<"Enter interest rate (percent per year): "; cin >>intrst_rate;
for(int i=0; i<num_year; i++) init_amount += init_amount*intrst_rate/100;
cout<<"At the end of "<<num_year
<<" years, you will have "<<init_amount
<<" dollars.";
cout<<"\n\n !Press c to continue or any key to exit."<<endl<<endl;
}while(getch()=='c');
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~*/

void main(void)
{
cout<<"### Programmed By Amahdy(MrJava) ,right restricted.~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n";
cout<<"------------------------\n"<<endl;

int i; float init_amount, intrst_rate, finl_amount;

do{
cout<<"Enter initial amount : "; cin >>init_amount;
cout<<"Enter interest rate (percent per year): "; cin >>intrst_rate;
cout<<"Enter final amount : "; cin >>finl_amount;
i=0;
while(finl_amount>=init_amount) {finl_amount -= finl_amount*intrst_rate/100; i++;}
cout<<"Number of years is : "<<i;
cout<<"\n\n !Press c to continue or any key to exit."<<endl<<endl;
}while(getch()=='c');
}

CHAPTER 4STRUCTURES

Questions:
----
1. A structure brings together a group of
a. items of the same data type.
b. related data items.
c. integers with user-defined names.
d. variables.
2. True or false: A structure and a class use similar syntax.
3. The closing brace of a structure is followed by a __________.
4. Write a structure specification that includes three variablesall of type intcalled hrs, mins, and secs. Call this structure time.
5. True or false: A structure declaration creates space in memory for a variable.
6. When accessing a structure member, the identifier to the left of the dot operator is the name of
a. a structure member.
b. a structure tag.
c. a structure variable.
d. the keyword struct.
7. Write a statement that sets the hrs member of the time2 structure variable equal to 11.
8. If you have three variables defined to be of type struct time, and this structure contains three int members, how many bytes of memory do the variables use together?
9. Write a definition that initializes the members of time1which is a variable of type struct time, as defined in Question 4to hrs = 11, mins = 10, secs = 59.
10. True or false: You can assign one structure variable to another, provided they are of the same type.
11. Write a statement that sets the variable temp equal to the paw member of the dogs member of the fido variable.
12. An enumeration brings together a group of
a. items of different data types.
b. related data variables.
c. integers with user-defined names.
d. constant values.
13. Write a statement that declares an enumeration called players with the values B1, B2, SS, B3, RF, CF, LF, P, and C.
14. Assuming the enum type players as declared in Question 13, define two variables joe and tom, and assign them the values LF and P, respectively.
15. Assuming the statements of Questions 13 and 14, state whether each of the following statements is legal.
a. joe = QB;
b. tom = SS;
c. LF = tom;
d. difference = joe - tom;
16. The first three enumerators of an enum type are normally represented by the values _________, _________, and _________.
17. Write a statement that declares an enumeration called speeds with the enumerators obsolete, single, and album. Give these three names the integer values 78, 45, and 33.
18. State the reason why
enum isWord{ NO, YES };
is better than
enum isWord{ YES, NO };
__________

My answers:
----
1. related data items, variables.
2. True.
3. ';'.
4. struct time {int hrs, mins, secs;};
5. False.
6. a structure variable.
7. time2.hrs=11;
8. 36.
9. time time1 = {11, 10, 59};
10. True.
11. temp=fido.dogs.paw;
12. integers with user-defined names, constant values.
13. enum players {B1, B2, SS, B3, RF, CF, LF, P, c};
14. players joe=LF, tom=P;
15. difference = joe - tom;
16. 0, 1, 2.
17. emun speeds {obsolete=78, single=45, album=33};
18. Normaly False is near to no and the first put in NO the same value of false, same thing for YES.
___________

Answers:
---
1. b, d
2. True
3. semicolon
4.
struct time
{
int hrs;
int mins;
int secs;
};

5. False; only a variable definition creates space in memory.
6. c
7. time2.hrs = 11;
8. 18 in 16-bit systems (3 structures times 3 integers times 2 bytes), or 36 in 32-bit systems
9. time time1 = { 11, 10, 59 };
10. True
11. temp = fido.dogs.paw;
12. c
13. enum players { B1, B2, SS, B3, RF, CF, LF, P, C };
14.
players joe, tom;
joe = LF;
tom = P;

15. a. No
b. Yes
c. No
d. Yes
16. 0, 1, 2
17. enum speeds { obsolete=78, single=45, album=33 };
18. Because false should be represented by 0.
________

/*6. We said earlier that C++ I/O statements dont automatically understand the data types of
enumerations. Instead, the (>>) and (<<) operators think of such variables simply as integers. You
can overcome this limitation by using switch statements to translate between the users way of
expressing an enumerated variable and the actual values of the enumerated variable. For example,
imagine an enumerated type with values that indicate an employee type within an organization:

enum etype { laborer, secretary, manager, accountant, executive,
researcher };

Write a program that first allows the user to specify a type by entering its first letter (l, s, m, and
so on), then stores the type chosen as a value of a variable of type enum etype, and finally displays
the complete word for this type.

Enter employee type (first letter only)
laborer, secretary, manager,
accountant, executive, researcher): a
Employee type is accountant.

Youll probably need two switch statements: one for input and one for output.*/
#include<iostream>
using namespace std;
#include<conio.h>

enum etype{laborer, secretary, manager, accountant, executive, researcher};
void main(void)
{
cout<<"### Programmed By Amahdy(MrJava) ,right restricted.~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n";
cout<<"------------------------\n"<<endl;

etype x; char *ret;

do{
cout<<"Enter employee type (first letter only)"<<endl
<<"(laborer, secretary, manager, accountant, executive, researcher): ";
switch(getche()){
case 'l': x=laborer ; break;
case 's': x=secretary ; break;
case 'm': x=manager ; break;
case 'a': x=accountant; break;
case 'e': x=executive ; break;
case 'r': x=researcher;}
switch(x){
case 0: ret = "laborer" ; break;
case 1: ret = "secretary" ; break;
case 2: ret = "manager" ; break;
case 3: ret = "accountant"; break;
case 4: ret = "executive" ; break;
case 5: ret = "researcher";}
cout<<"\nEmployee type is "<<ret<<".";
cout<<"\n\n !Press c to continue or any key to exit."<<endl<<endl;
}while(getch()=='c');
}

/*7. Add a variable of type enum etype (see Exercise 5), and another variable of type struct date (see
Exercise 3) to the employee class of Exercise 4. Organize the resulting program so that the user
enters four items of information for each of three employees: an employee number, the employees
compensation, the employee type, and the date of first employment. The program should store this
information in three variables of type employee, and then display their contents.*/
#include<iostream>
#include<conio.h>
#include<iomanip>
using namespace std;

enum etype{laborer, secretary, manager, accountant, executive, researcher};
struct date{int day; int month; int year;};
struct employee{int number; float compensation; date d; char *ret;};
void main(void)
{
cout<<"### Programmed By Amahdy(MrJava) ,right restricted.~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n";
cout<<"------------------------\n"<<endl;

employee e[3]; int i; char c; etype x;
do{
for(i=0; i<3; i++) {
cout<<"\nEnter the number of employee number "<<i+1<<" : "; cin>>e[i].number;
cout<<"Enter the compensation of employee number "<<i+1<<" : "; cin>>e[i].compensation;
cout<<"Enter employee type (first letter only) of employee number "<<i+1<<" : "<<endl
<<"(laborer, secretary, manager, accountant, executive, researcher): ";
switch(getche()){
case 'l': x=laborer ; break;
case 's': x=secretary ; break;
case 'm': x=manager ; break;
case 'a': x=accountant; break;
case 'e': x=executive ; break;
case 'r': x=researcher;}
switch(x){
case 0: e[i].ret = "laborer" ; break;
case 1: e[i].ret = "secretary" ; break;
case 2: e[i].ret = "manager" ; break;
case 3: e[i].ret = "accountant"; break;
case 4: e[i].ret = "executive" ; break;
case 5: e[i].ret = "researcher"; break;
default: e[i].ret = "Unknow";}
cout<<"\nEnter the date of employee number "<<i+1<<" : "; cin >>e[i].d.day>>c>>e[i].d.month>>c>>e[i].d.year;}
cout<<"\nEmployee number"<<" compensation"<<" type"<<" date of first employment"<<endl;
for(i=0; i<3; i++) cout<<setw(15)<<e[i].number
<<setw(15)<<e[i].compensation
<<setw(15)<<e[i].ret
<<setw(21)<<e[i].d.day<<c<<e[i].d.month<<c<<e[i].d.year<<endl;
cout<<"\n\n !Press c to continue or any key to exit."<<endl<<endl;
}while(getch()=='c');
}

/*8. Start with the fractionadding program of Exercise 9 in Chapter 2, C++ Programming Basics.
This program stores the numerator and denominator of two fractions before adding them, and may
also store the answer, which is also a fraction. Modify the program so that all fractions are stored in
variables of type struct fraction, whose two members are the fractions numerator and denominator
(both type int). All fraction-related data should be stored in structures of this type.*/
#include<iostream>
#include<conio.h>
using namespace std;

struct fraction{int numerator; int denominator;};
void main(void)
{
cout<<"### Programmed By Amahdy(MrJava) ,right restricted.~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n";
cout<<"------------------------\n"<<endl;
fraction equ[2];
char operation;

do{
cout<<"Enter first fraction: ";
cin >>equ[0].numerator>>operation>>equ[0].denominator; //if (operation != '/') {raise error event}
cout<<"Enter second fraction: ";
cin >>equ[1].numerator>>operation>>equ[1].denominator; //if (operation != '/') {raise error event}
cout<<"Sum = "<<(equ[0].numerator*equ[1].denominator+equ[0].denominator*equ[1].numerator)
<<operation<<(equ[0].denominator*equ[1].denominator)<<endl;
cout<<"\n\n !Press c to continue or any key to exit."<<endl<<endl;
}while(getch()=='c');
}

/*9. Create a structure called time. Its three members, all type int, should be called hours, minutes, and
seconds. Write a program that prompts the user to enter a time value in hours, minutes, and seconds.
This can be in 12:59:59 format, or each number can be entered at a separate prompt (Enter
hours:, and so forth). The program should then store the time in a variable of type struct time, and
finally print out the total number of seconds represented by this time value:

long totalsecs = t1.hours*3600 + t1.minutes*60 + t1.seconds
*/
#include<iostream>
#include<conio.h>
using namespace std;

struct time{int hours; int minutes; int seconds;};
void main(void)
{
cout<<"### Programmed By Amahdy(MrJava) ,right restricted.~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n";
cout<<"------------------------\n"<<endl;

time t1; char c;

do{
cout<<"Enter a time value in hours, minutes, and seconds [hh:mm:ss] format: ";
cin >>t1.hours>>c>>t1.minutes>>c>>t1.seconds;
cout<<"The total number of seconds is: "<<t1.hours*3600 + t1.minutes*60 + t1.seconds;
cout<<"\n\n !Press c to continue or any key to exit."<<endl<<endl;
}while(getch()=='c');
}

/*10. Create a structure called sterling that stores money amounts in the old-style British system
discussed in Exercises 8 and 11 in Chapter 3, Loops and Decisions. The members could be
called pounds, shillings, and pence, all of type int. The program should request the user to enter a
money amount in new-style decimal pounds (type double), convert it to the old-style system, store it
in a variable of type struct sterling, and then display this amount in pounds-shillings-pence format.*/
#include<iostream>
#include<conio.h>
using namespace std;

struct sterling{int pounds; int shillings; int pence;};
void main(void)
{
cout<<"### Programmed By Amahdy(MrJava) ,right restricted.~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n";
cout<<"------------------------\n"<<endl;

float decpounds; float decfrac; //From old programme.
sterling s1;

do{
cout<<"Enter a money amount in new-style decimal pounds: ";
cin >>decpounds;
s1.pounds = static_cast<int>(decpounds);
decfrac = 240*(decpounds-s1.pounds);
s1.shillings = (static_cast<int>(decfrac))%12; //Ignore fracions in pence.
decfrac = static_cast<int>((decfrac-s1.shillings)/12); //Ignore fracions in pence.
cout<<"Equivalent in old notation = \x9c"<<s1.pounds<<"."<<decfrac<<"."<<s1.shillings<<endl;
cout<<"\n\n !Press c to continue or any key to exit."<<endl<<endl;
}while(getch()=='c');
}

CHAPTER 5FUNCTIONS

Questions:
----
1. A functions single most important role is to
a. give a name to a block of code.
b. reduce program size.
c. accept arguments and provide a return value.
d. help organize a program into conceptual units.
2. A function itself is called the function d_________.
3. Write a function called foo() that displays the word foo.
4. A one-statement description of a function is referred to as a function d_________ or a p_________.
5. The statements that carry out the work of the function constitute the function _________.
6. A program statement that invokes a function is a function _________.
7. The first line of a function definition is referred to as the _________.
8. A function argument is
a. a variable in the function that receives a value from the calling program.
b. a way that functions resist accepting the calling programs values.
c. a value sent to the function by the calling program.
d. a value returned by the function to the calling program.
9. True or false: When arguments are passed by value, the function works with the original arguments in the calling program.
10. What is the purpose of using argument names in a function declaration?
11. Which of the following can legitimately be passed to a function?
a. A constant
b. A variable
c. A structure
d. A header file
12. What is the significance of empty parentheses in a function declaration?
13. How many values can be returned from a function?
14. True or false: When a function returns a value, the entire function call can appear on the right side of the equal sign and be assigned to another variable.
15. Where is a functions return type specified?
16. A function that doesnt return anything has return type _________.
17. Heres a function:
int times2(int a)
{
return (a*2);
}

Write a main() program that includes everything necessary to call this function.
18. When an argument is passed by reference,
a. a variable is created in the function to hold the arguments value.
b. the function cannot access the arguments value.
c. a temporary variable is created in the calling program to hold the arguments value.
d. the function accesses the arguments original value in the calling program.
19. What is a principle reason for passing arguments by reference?
20. Overloaded functions
a. are a group of functions with the same name.
b. all have the same number and types of arguments.
c. make life simpler for programmers.
d. may fail unexpectedly due to stress.
21. Write declarations for two overloaded functions named bar(). They both return type int. The first takes one argument of type char, and the second takes two arguments of type char. If this is impossible, say why.
22. In general, an inline function executes _________ than a normal function, but requires _________ memory.
23. Write the declarator for an inline function named foobar() that takes one argument of type float and returns type float.
24. A default argument has a value that
a. may be supplied by the calling program.
b. may be supplied by the function.
c. must have a constant value.
d. must have a variable value.
25. Write a declaration for a function called blyth() that takes two arguments and returns type char. The first argument is type int, and the second is type float with a default value of 3.14159.
26. Storage class is concerned with the _________ and _________ of a variable.
27. What functions can access an external variable that appears in the same file with them?
28. What functions can access an automatic variable?
29. A static automatic variable is used to
a. make a variable visible to several functions.
b. make a variable visible to only one function.
c. conserve memory when a function is not executing.
d. retain a value when a function is not executing.
30. In what unusual place can you use a function call when a function returns a value by reference?
__________

My answers:
----
1. reduce program size, help organize a program into conceptual units.
2. definition.
3. void foo(void) {cout<<"foo"; }
4. declairation, property value.
5. work.
6. caller.
7. function name.
8. a variable in the function that receives a value from the calling program, a value sent to the function by the calling program.
9. False.
10. Facilite knowing the concept of argument that I'll pass to the function.
11. A constant, A variable, A structure.
12. void.
13. one.
14. True.
15. before it's name.
16. void.
17. void main(void) {int a, time_two=times2(a);}
18. the function accesses the arguments original value in the calling program.
19. Use the original variable, not copy large values & return many different parammeters.
20. are a group of functions with the same name, make life simpler for programmers.
21. int bar(char); int bar(char, char);
22. faster, more.
23. inline float foobar(float);
24. may be supplied by the calling program, may be supplied by the function.
25. char blyth(int, float=3.14159);
26. ?, ?.
27. All defined function.
28. Functions that contains in their variables definition the "auto" keyword.
29. retain a value when a function is not executing.
30. As assigned value to it.
___________

Answers:
---
1. d (half credit for b)
2. definition
3.
void foo()
{
cout << foo;
}

4. declaration, prototype
5. body
6. call
7. declarator
8. c
9. False
10. To clarify the purpose of the arguments.
11. a, b, c
12. Empty parentheses mean the function takes no arguments.
13. one
14. True
15. At the beginning of the declaration and declarator.
16. void
17.
main()
{
int times2(int); // prototype
int alpha = times2(37); // function call
}

18. d
19. To modify the original argument (or to avoid copying a large argument).
20. a, c
21.
int bar(char);
int bar(char, char);

22. faster, more
23. inline float foobar(float fvar)
24. a, b
25. char blyth(int, float=3.14159);
26. visibility, lifetime
27. Those functions defined following the variable definition.
28. The function in which it is defined.
29. b, d
30. On the left side of the equal sign.
________

/*6. Start with the program from Exercise 11, Chapter 4, Structures, which adds two struct time
values. Keep the same functionality, but modify the program so that it uses two functions. The first,
time_to_secs(), takes as its only argument a structure of type time, and returns the equivalent in
seconds (type long). The second function, secs_to_time(), takes as its only argument a time in
seconds (type long), and returns a structure of type time. */
#include<iostream>
#include<conio.h>
using namespace std;

struct time{int hours; int minutes; int seconds;};
long time_to_secs(time t);
time secs_to_time(long s);

void main(void)
{
cout<<"### Programmed By Amahdy(MrJava) ,right restricted.~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n";
cout<<"------------------------\n"<<endl;

time t1, t2, t3; char c;

do{
cout<<"In [hh:mm:ss] format;\n";
cout<<"Enter first time value : "; cin >>t1.hours>>c>>t1.minutes>>c>>t1.seconds;
cout<<"Enter second time value: "; cin >>t2.hours>>c>>t2.minutes>>c>>t2.seconds;
t3=secs_to_time(time_to_secs(t1)+time_to_secs(t2));
cout<<"The result is: "<<t3.hours<<":"<<t3.minutes<<":"<<t3.seconds;
cout<<"\n\n !Press c to continue or any key to exit."<<endl<<endl;
}while(getch()=='c');
}

long time_to_secs(time t){ return t.hours*3600+t.minutes*60+t.seconds;}
time secs_to_time(long s){
time t;
t.seconds=s%60; t.minutes=((s-t.seconds)%3600)/60; t.hours=s/3600;
if(t.seconds>59) {t.seconds-=59; t.minutes++;} //Check seconds over.
if(t.minutes>59) {t.minutes-=59; t.hours++;} //Check minutes over.
return t;
}

/*7. Start with the power () function of Exercise 2, which works only with type double. Create a series
of overloaded functions with the same name that, in addition to double, also work with types char,
int, long, and float. Write a main() program that exercises these overloaded functions with all
argument types.*/
#include<iostream>
#include<conio.h>
using namespace std;

double power(double n, int p=2);
char power(char n, int p=2);
int power(int n, int p=2);
long power(long n, int p=2);
float power(float n, int p=2);

void main(void)
{
cout<<"### Programmed By Amahdy(MrJava) ,right restricted.~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n";
cout<<"------------------------\n"<<endl;

char sep; int p=2; double d_n; char c_n; int i_n; long l_n; float f_n;

do{
cout<<"In [n^p] format;\n";
cout<<"Enter a double type n : "; cin >>d_n>>sep>>p;
cout<<"The power is "<<power(d_n, p)<<endl;
cout<<"Enter a char type n : "; cin >>c_n>>sep>>p;
cout<<"The power is "<<power(c_n, p)<<endl;
cout<<"Enter a int type n : "; cin >>i_n>>sep>>p;
cout<<"The power is "<<power(i_n, p)<<endl;
cout<<"Enter a long type n : "; cin >>l_n>>sep>>p;
cout<<"The power is "<<power(l_n, p)<<endl;
cout<<"Enter a float type n : "; cin >>f_n>>sep>>p;
cout<<"The power is "<<power(f_n, p)<<endl;
cout<<"\n\n !Press c to continue or any key to exit."<<endl<<endl;
}while(getch()=='c');
}

double power(double n, int p){ for(int ret=1; p>0; p--) ret*=n; return ret;}
char power(char n, int p){ for(int ret=1; p>0; p--) ret*=n; return ret;}
int power(int n, int p){ for(int ret=1; p>0; p--) ret*=n; return ret;}
long power(long n, int p){ for(int ret=1; p>0; p--) ret*=n; return ret;}
float power(float n, int p){ for(int ret=1; p>0; p--) ret*=n; return ret;}

/*8. Write a function called swap() that interchanges two int values passed to it by the calling program.
(Note that this function swaps the values of the variables in the calling program, not those in the
function.) Youll need to decide how to pass the arguments. Create a main() program to exercise the
function.*/
#include<iostream>
#include<conio.h>
using namespace std;

void swap(int& a, int& b);

void main(void)
{
cout<<"### Programmed By Amahdy(MrJava) ,right restricted.~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n";
cout<<"------------------------\n"<<endl;

int a, b;

do{
cout<<"Enter a : "; cin >>a;
cout<<"Enter b : "; cin >>b; swap(a, b);
cout<<"Now a value is : "<<a<<" and b value is : "<<b;
cout<<"\n\n !Press c to continue or any key to exit."<<endl<<endl;
}while(getch()=='c');
}

void swap(int& a, int& b){int c=a; a=b; b=c;}

/*9. This exercise is similar to Exercise 8, except that instead of two int variables, have the swap()
function interchange two struct time values (see Exercise 6).*/
#include<iostream>
#include<conio.h>
using namespace std;

struct time{int hours; int minutes; int seconds;};
void swap(time& t1, time& t2);

void main(void)
{
cout<<"### Programmed By Amahdy(MrJava) ,right restricted.~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n";
cout<<"------------------------\n"<<endl;

time t1, t2; char c;

do{
cout<<"In [hh:mm:ss] format;\n";
cout<<"Enter first time value : "; cin >>t1.hours>>c>>t1.minutes>>c>>t1.seconds;
cout<<"Enter second time value: "; cin >>t2.hours>>c>>t2.minutes>>c>>t2.seconds;
swap(t1, t2);
cout<<"Now first time is : " <<t1.hours<<c<<t1.minutes<<c<<t1.seconds
<<" and second time is : "<<t2.hours<<c<<t2.minutes<<c<<t2.seconds;
cout<<"\n\n !Press c to continue or any key to exit."<<endl<<endl;
}while(getch()=='c');
}

void swap(time& a, time& b){time c=a; a=b; b=c;}

/*10. Write a function that, when you call it, displays a message telling how many times it has been
called: I have been called 3 times, or whatever. Write a main() program that calls this function at
least 10 times. Try implementing this function in two different ways. First, use an external variable to
store the count. Second, use a local static variable. Which is more appropriate? Why cant you use
an automatic variable?*/
#include<iostream>
#include<conio.h>
using namespace std;

void caller_counter(void);

void main(void)
{
cout<<"### Programmed By Amahdy(MrJava) ,right restricted.~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n";
cout<<"------------------------\n"<<endl;

int outer_counter=0;

do{
outer_counter++; caller_counter();
cout<<"\nThe main programme counter value is: "<<outer_counter;
cout<<"\n\n !Press c to continue or any key to exit."<<endl<<endl;
}while(getch()=='c');
}

void caller_counter(void){
//I can't use an automatic variable coz it's created once I call the function only.
static int inner_counter=0; inner_counter++;
cout<<"I have been called "<<inner_counter<<" times";}

CHAPTER 6OBJECTS AND CLASSES

Questions:
----
1. What is the purpose of a class declaration?
2. A ________ has the same relation to an ________ that a basic data type has to a variable of that type.
3. In a class declaration, data or functions designated private are accessible
a. to any function in the program.
b. only if you know the password.
c. to member functions of that class.
d. only to public members of the class.
4. Write a class declaration that creates a class called leverage with one private data member, crowbar, of type int and one public function whose declaration is void pry().
5. True or false: Data items in a class must be private.
6. Write a statement that defines an object called lever1 of the leverage class described in Question 4.
7. The dot operator (or class member access operator) connects the following two entities (reading from left to right):
a. A class member and a class object
b. A class object and a class
c. A class and a member of that class
d. A class object and a member of that class
8. Write a statement that executes the pry() function in the lever1 object, as described in Questions 4 and 6.
9. Member functions defined inside a class declaration are ________ by default.
10. Write a member function called getcrow() for the leverage class described in Question 4. This function should return the value of the crowbar data. Assume the function is defined within the class declaration.
11. A constructor is executed automatically when an object is ________.
12. A constructors name is the same as _________.
13. Write a constructor that initializes to 0 the crowbar data, a member of the leverage class described in Question 4. Assume the constructor is defined within the class declaration.
14. True or false: In a class you can have more than one constructor with the same name.
15. A member function can always access the data
a. in the object of which it is a member.
b. in the class of which it is a member.
c. in any object of the class of which it is a member.
d. in the public part of its class.
16. Assume the member function getcrow() described in Question 10 is defined outside the class declaration. Write the declaration that goes inside the class declaration.
17. Write a revised version of the getcrow() member function from Question 10 that is defined outside the class declaration.
18. The only technical difference between structures and classes in C++ is that _________.
19. If three objects of a class are defined, how many copies of that classs data items are stored in memory? How many copies of its member functions?
20. Sending a message to an object is the same as _________.
21. Classes are useful because they
a. are removed from memory when not in use.
b. permit data to be hidden from other classes.
c. bring together all aspects of an entity in one place.
d. can closely model objects in the real world.
22. True or false: There is a simple but precise methodology for dividing a realworld programming problem into classes.
23. For the object for which it was called, a const member function
a. can modify both const and nonconst member data.
b. can modify only const member data.
c. can modify only nonconst member data.
d. can modify neither const nor nonconst member data.
24. True or false: If you declare a const object, it can only be used with const member functions.
25. Write a declaration (not a definition) for a const void function called aFunc() that takes one const argument called jerry of type float.
__________

My answers:
----
1. Manage objects formation.
2. Class, Object.
3. to member functions of that class.
4. class leverage{int crowbar; public: void pry();};
5. False.
6. leverage lever1;
7. A class object and a member of that class.
8. lever1.pry();
9. private.
10. int getcrow(){ return crowbar;}
11. defined.
12. class.
13. levrage(): crowbar(0){}
14. True.
15. in the object of which it is a member.
16. int getcrow();
17. int leverage::getcrow(){ return crowbar;}
18. members are by default public in struct, and private in class.
19. 3, 1.
20. passing to a function.
21. permit data to be hidden from other classes, bring together all aspects of an entity in one place, can closely model objects in the real world.
22. True.
23. can modify neither const nor nonconst member data.
24. False.
25. void aFunc(const float jerry) const;
___________

Answers:
---
1. A class declaration describes how objects of a class will look when they are created.
2. class, object
3. c
4.
class leverage
{
private:
int crowbar;
public:
void pry();
};

5. False; both data and functions can be private or public.
6. leverage lever1;
7. d
8. lever1.pry();
9. inline (also private)
10.
int getcrow()
{ return crowbar; }

11. created (defined)
12. the class of which it is a member
13.
leverage()
{ crowbar = 0; }

14. True
15. a
16. int getcrow();
17.
int leverage::getcrow()
{ return crowbar; }

18. member functions and data are, by default, public in structures but private in classes
19. three, one
20. calling one of its member functions
21. b, c, d
22. False; trial and error may be necessary.
23. d
24. True
25. void aFunc(const float jerry) const;
________