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4.2 THE if-else STATEMENT 4.3 NESTED if STATEMENT 4.4 THE switch STATEMENT 4.5 CONDITIONAL EXPRESSIONS 4.6 THE enum SPECIFIER

Chapter 5 REPITITION STRUCTURES 5.1 INTRODUCTION 5.2 while LOOPS 5.3 INTERACTIVE while LOOP 5.4 for LOOPS 5.5 NESTED LOOPS 5.6 do-while LOOPS 5.7 STRUCTURED PROGRAMMING WITH C++ 5.8 ARRAYS 5.9 STRUCTURES

Chapter 6 MODULARITY USING FUNCTIONS 6.1 FUNCTION AND PARAMETER DECLARATIONS 6.2 RETURNING VALUES 6.3 VARIABLE SCOPE 6.4 VARIABLE STORAGE CLASS. 6.5 PASS BY REFERENCE USING REFERENCEPARAMETERS 6.6 RECURSION 6.7 PASSING ARRAYS TO FUNCTIONS 6.8 POINTERS


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6.9 PASSING STRUCTURES as PARAMETERS 6.10 THE typedef DECLARATION STATEMENT

Chapter 7 INTRODUCTION TO CLASSES 7.1 STACK VERSUS HEAP

7.2 OBJECT ORIENTED PROGRAMMING AND CLASSES 7.3 INFORMATION HIDING 7.4 MEMBER FUNCTIONS

Chapter 8 OBJECT MANIPULATION 8.1 ADVANCED CONSTRUCTORS

8.2 DESTRUCTORS 8.3 ASSIGNMENT 8.4 CONSTANT OBJECTS 8.5 STATIC CLASS MEMBERS

Chapter 9 INHERITANCE POLYMORPHISM -TEMPLATE

9.1 BASIC INHERITANCE 9.2 OVERRIDDING BASE CLASS MEMBER FUNCTIONS 9.3 CONSTRUCTORS AND DESTRUCTORS IN DERIVEDCLASSES 9.4 POLYMORPHISM 9.5 TEMPLATES 9.6 PURE VIRTUAL FUNCTIONS AND ABSTRACT BASECLASSES


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Chapter 1 INTRODUCTION TO COMPUTER AND

PROGRAMMING

1.1 HARDWARE AND SOFTWARE

1.1.1 Computer HardwareA computer may be divided into six logical units.

Input Unit y O btain information from input devices: keyboards and mouse

devices.y Place the information at the disposal of the other units to be

processed.

Output Unit y Take information that has been processed.y Place it on output devices: displayed on screens, printed on

paper.

Mem ory Unit y RA M ( random access memory ) is volatile, stores program and

data.y RO M ( read only memory ) is non-volatile, contains fundamental

instructions.

A rith me tic and Logic Unit ( A LU)

y Perform all the arithmetic and logic operations: addition,subtraction, comparison, etc..


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CP U y Tell the input unit when information should be read into the

memory unit.y Tell the ALU when information from the memory should be

used in calculations.y Tell the output unit when to send information from the memory

unit to certain output devices.

S econdary S torag e .y Permanent storage areas for programs and data: magnetic tapes,

magnetic hard disks, floppy disk, CD RO M

1.1.2 Computer Softwarey A com put er progra m: set of instructions used to operate a

computer to produce a specific result.y C om put er progra mm ing : writing computer programs.y P rogra mm ing languag es: languages used to create computer

programs.

M achin e Languag esExample: 0101010 000000000001 000000000010

y The lowest level of computer languages.y Programs consist of entirely of 1s and 0s.y Programs can control directly to the computers hardware.y Machine language instructions consist of two parts:

o I nstruction part ( opcode ) is the leftmost group of bits andtells the computer the operation to be performed.

o A ddress part specifies the memory address of the data to beused in the instruction.


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A ssemb ly Languag es

Example:LOA D B AS EPAY ADD OV ER PAY STOR E G ROSS PAY

y Perform the same tasks as machine languages, but use symb olicna me s for opcodes and operands.

y An assembly language program must be translated into amachine language program.

y Machine languages and assembly languages are called low-l eve l languag es since they are clos est to co m put er hardwar e.

H igh-l eve l P rogra mm ing Languag es

y Create computer programs using instructions that much easier to understand: E nglish-lik e included with mathematicalnotations.

y Programs written in high-level languages must be translatedinto a low level language using a program called a co m pil er .

y Each line in a high-level language program is called a

statement .Ex: R esult = (First + Second)* Third.

A pplication and S yst em S oftwar e y A pplication software: perform particular tasks required by the

users.

Translation program(assembler)

Assemblylanguage program

Machinelanguage program


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y S ystem software: must be available to any computer system tooperate. The most important system software is the operating

system (MS-DOS , UN IX , MS WI NDOWS , MS W I NDOWS NT )

y Mu ltitasking systems: operating systems allow user to run

multiple programs.1.2 PROGRAMMING LANGUAGESFORTRAN 1957COBOL 1960sBAS I C 1960sPAS CAL 1971 Structure programmingCC++C and C++ are two separate, but related programming languages.I n the 1970s, at Bell Laboratories, Dennis R itchie and BrianKernighan designed the C programming language.In 1985, at Bell Laboratories, Bjarne Stroutrup created C++ basedon the C language. C++ is an extension of C that adds object-

oriented programming capabilities.

W hat is S yntax?y Set of rules for writing grammatically correct language

statements.

1.2.1 The C Programming Languagey C was used exclusively on UN IX and on mini-computers.

During the 1980s, C compilers were written for other flatforms,including PCs.


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y To provide a level of standardization for C language, in 1989,ANS I created a standard version of C that is called AN S I C .

y One m ain be ne fit of the C language is that it is much clos er toass emb ly languag e other than other types of high-level

programming languages. The programs written in C often run

much fast er and more efficiently.1.2.2 The C++ Programming Language

y C++ is now the most popular programming language for writinggraphical programs that run on Windows and Macintosh.

y The standardized version of C++ is commonly referred to as AN S I C++ .

y The ANS I standards also define run-ti me li brari es, whichcontains useful functions, variables, constants, and other

programming items that you can add to your programs.y The ANS I C++ run-time library is also called the S tandard

T em plat e Li brary or Standard C++ Library.

1.2.3 Microsoft Visual C++y Actually, V isual C++ itself is not a programming language. I t is

a d eve lop me nt environ me nt used for creating programs withthe C/C++ languages.

y V isual C++ extends the C++ language by allowing you toinclude M icrosoft Foundation C lass es in your programs.

1.3 PROBLEM SOLUTION AND SOFTWAREDEVELOPMENT

Software development consists of three overlapping phases:y Development and Designy Documentation


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P has e III : M aint enanc e This phase is concerned with the ongoing correction of problems,revisions to meet changing needs and the addition of new features.

1.4 ALGORITHMS

1.4.1 FlowchartsA flowchart is an outlin e of the basic structur e or logic of the

program.

Terminal

I nput/output

Process

Flow lines

Decision

Connector


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Predefined process

Note: Name, Hours and Pay are variables in the program.

1.4.2 Pseudo-codeYou also can use English-like phases to desribe an algorithm. I n thiscase, the description is called pse u do-code .

Inp u t the three val u es into the variables Name, Ho u rs, Rate.

Calc u late Pay = Ho u rs v Rate. Display Name and Pay.

Problem 1.Write a program to do the following task: Print a list of the numbersfrom 4 to 9. Next to each number, print the square of the number.

Start

Input Name,H ur Rate

CalculatePay n Hours v Rate

DisplayName, Pay

End


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Note:

1. Loop is a very important concept in programming.2. Num n Num + 1

New value of Num = old value of Num + 1.

Start

NUM n 4

SQNUM n NUM 2

PrintNUM, SQNUM

NUM n NUM + 1

NUM


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Since flowcharts are inconvenient to revise, they have fallen out of favor by programmers. Nowadays, the use of pseudocode has gainedincreasing acceptance.


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Chapter 2 PROBLEM SOLVING USING C++

2.1 INTRODUCTION TO C++

2.1.1 Modular Programsy M odul es: interrelated segments, arranged in a logical order.y A program that consists of such modules is called a modular

program.y I n C++ , modules can be class es or functions .

Function : transform the data it receives into a result. Each function

must have a name. Names or id entifi ers in C++ can made up of anycombination of letters, digits, or underscores selected according tothe following rules:

y I dentifiers must begin within an uppercase or lowercase AS CII letter or an underscore (_).

y You can use digits in an identifier, but not as the first character.Y

ou are not allowed to use special characters such as $, &, * or %.y R eserved words cannot be used for variable names.

Examples of valid identifiers:Deg ToR ad intersect add NumsFindMax1 _density slope

Examples of invalid identifiers:1AB3 E%6 while

Note: C++ is a cas e-sensiti ve language.


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2.1.2 The m ain() functiony The m ain () function: runs automatically when a program first

executes.y C++ programs must include on e m ain() function. A ll other

functions in a C++ program are executed from the main () function.

The first line of the function, in this case void main () is called a function h ead er lin e.The f u nction header line contains three pieces of information:

1. What type of data, if any, is returned from the function?2. The name of the function.3. What type of data, if any, is sent into the function?

int main(){

program statements in herereturn 0;

}O r void main(){

program statements in here}

2.1.3 The cout ObjectThe co u t object: an output object that sends data given to it to thestandard output display device.

cout


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The ins ertion op erator ,


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C++ stat eme nts writing syntax : A ll statements in C++ must end with a s em icolon .Large statements can span m ultipl e lin es of cod e:cout


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y There are three basic data types used in C++: integers, floating point numbers and characters.

Int e g ersy An integer is a positive or negative number with no decimal

places.- 259 -13 0 200

Floating P oint N umbe rsy A floating point number contains decimal places or is written

using exponential notations.-6.16 -4.4 2.7541 10.5

y Ex ponential notation or scientific notation is a way of writing avery large numbers or numbers with many decimal places usinga shortened format.2.0e11 means 2*10 11

y C++ supports three different kinds of floating-point numbers:o float (i.e. single precision numbers),o double (i.e. double precision numbers)o long double.

Th e C haract er Data Typ e y To store text, you use the character data type. To store one

character in a variable, you use the char keyword and place thecharacter in single quotation marks.

char letter = A;

E scap e S eq uenc e The combination of a backlash (\) and a special character is calledan escape sequence.


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\n move to the next line\t move to the next tab

2.3.2 Arithmetic OperatorsO perator Description

---------------------------------------------------------------+ Add two operands- Subtracts one operand from another operand* Multiplies one operand by another operand/ Divides one operand by another operand% Divides two operands and returns the remainder

A simple arithmetic expression consists of an arithmetic operator connecting two operands in the form:

operand operator operand

3 + 712.62 + 9.812.6/2.0

Example 2.3.1# include void main(){

cout


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Int e g er Di vision

Th e di vision of two int e g ers yields integer result. Thus the value of 15/2 is 7.

15.0/2 is ???Modulus % operator produces the remainder of an integer division.

9%4 is 117%3 is 214%2 is 0

O perator P r eced enc e and A ssociati vity

Expressions containing multiple operators are evaluated by the

priority, or precedence , of the operators.The following table lists both precedence and associativity of theoperators.

O perator Associativity---------------------------------unary - R ight to left

* / % Left to right+ - Left to right

8 + 5*7%2*4q q q q

4 1 2 3

2.4 VARIABLES AND DECLARATION STATEMENTSOne of the most important aspects of programming is storing and manipulating the values stored in variables .V aria bl e na me s are also selected according to the rules of identifiers:


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y I dentifiers must be gin with an uppercase or lowercase AS CII letter or an underscore (_).

y You can use digits in an identifier, but not as the first character.You are not allowed to use sp ecial charact ers such as $, &, * or %.

y R eser ved words cannot be used for variable names.Example: Some valid identifiers

my_variable Temperature x1x2 _my_variable

Some in valid identifiers are as follows:%x1 %my_var @x2

2.4.1 Declaration StatementsI n C++ you can declare the data types of variables using the syntax:

type na me; The type portion refers to the data type of the variable. The data typedetermines the type of information that can be stored in the variable.

Example:int sum;long datenem;double secnum;

Note:1. A varia bl e must be d eclar ed be for e it can be us ed .2. Declaration statements can also be used to store an initial valu e

into declared variables.Example:

int num = 15;


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float grade1 = 87.0;Example 2.4.1# include void main(){

float grade1 = 85.5;float grade2 = 97.0;float total, average;total = grade1 + grade2;average = total/2.0; // divide the total by 2.0cout


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num = 22;cout


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Name Namesint * signed,

signed intSystem dependent

unsignedint

* unsigned System dependent

bool 1 none false or truechar 1 signed char 128 to 127unsignedchar

1 none 0 to 255

short 2 short int,signed shortint

32,768 to 32,767

unsignedshort

2 unsignedshort int

0 to 65,535

long 4 long int,signed longint

2,147,483,648 to 2,147,483,647

long long 8 none (butequivalent to

__int64)

9,223,372,036,854,775,808 to9,223,372,036,854,775,807

unsignedlong

4 unsignedlong int

0 to 4,294,967,295

enum * none Same as intfloat 4 none 3.4E +/- 38 (7 digits)double 8 none 1.7E +/- 308 (15 digits)

long double same asdouble none same as double

wchar_t 2 __wchar_t 0 to 65,535

The limits for integer types are listed in the following table. Theselimits are defined in the standard header file LI M IT S . H .


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Limits on Integer Constants

Constant Meaning ValueSCHAR_MIN Minimum value for a

variable of type signedchar .

128

SCHAR_MAX Maximum value for avariable of type signedchar .

127

UCHAR_MAX Maximum value for avariable of type unsignedchar .

255 (0xff)

CHAR_MIN Minimum value for avariable of type char .

128

CHAR_MAX Maximum value for avariable of type char .

127

SHRT_MIN Minimum value for avariable of type short .

32768

SHRT_MAX Maximum value for a

variable of type short .

32767

USHRT_MAX Maximum value for avariable of type unsignedshort .

65535 (0xffff)

INT_MIN Minimum value for avariable of type int .

2147483647 1

INT_MAX Maximum value for a

variable of type int .

2147483647

UINT_MAX Maximum value for avariable of type unsignedint .

4294967295 (0xffffffff)

LONG_MIN Minimum value for a 2147483647 1


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variable of type long .LONG_MAX Maximum value for a

variable of type long .2147483647

ULONG_MAX Maximum value for avariable of type unsigned

long .

4294967295 (0xffffffff)

2.4.4 Data Type Conversionsy An expression that contains only integer operands is called an

int e g er e xpr ession , and the result of the expression is an integer value.

y An expression that contains only floating point operands (single

and double precision) is called a floating point e xpr ession , andthe result of such an expression is a floating point value.

y An expression containing both integer and floating pointoperands is called a m ix ed m od e e xpr ession .

The general rul es for con verting integer and floating pointoperands in mixed mode arithmetic expressions were presented asfollows:1. I f both op erands are either charact er or int e g er operands:

a. when both operands are charact er , short or integer datatypes, the result of the expression is an integer value.

b. when one of the operand is a long int e g er , the result is a longinteger, unless one of the operand is an unsign ed int e g er . I nthe later case, the other operand is converted to an unsignedinteger value and the resulting value of the expression is anunsigned value.

2. I f any one op erand is a floating point value:a. when one or both operands are floats, the result of the

operation is a float value;


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b. when one or both operands are doubles, the result of theoperation is a double value;

c. when one or both operands are long doubles, the result of theoperation is a long double value;

2.4.5 Determing Storage SizeC++ provides an operator for determining the amount of storageyour compiler allocates for each data type. This operator, called thesiz eof() operator.

sizeof(num1)sizeof(int)sizeof(float)

The item in parentheses can be a varia bl e or a data typ e .

# include void main(){

char ch;short int num1;cout


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Bytes of storage used by a short integer: 2

2.5 SOME SAMPLE PROGRAMS

2.5.1 Computing the circumference of a circle

C = 2 Tr


float radius, circumference;radius = 2.0;circumference = 2.0 * 3.1416 * radius;

cout


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Chapter 3 COMPLETING THE BASICS

3.1 ASSIGNMENT OPERATORS A ssignment operator (=) are used for assignment a value to a

variable and for performing computations.Assignment statement has the syntax:varia bl e = e xpr ession ;

Ex pression is any combination of constants, variables, and functioncalls that can be evaluated to yield a result.

length = 25;

cMyCar = Mercedes;sum = 3 + 7;newtotal = 18.3*amount;slope = (y2 y1)/(x2 x1)

I ts important to note that the eq ual sign in C ++ does not have thesame meaning as an equal sign in mathematics.

Example 3.1// this program calculates the volume of a cylinder,// given its radius and height# include void main(){

float radius, height, volume;radius = 2.5;height = 16.0;volume = 3.1416 * radius * radius * height;cout


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}The output of the above program:The volume of the cylinder is 314.16 Note:

We can write m ultipl e assign me nts : a = b = c = 25;

A ssign me nt V ariations

C++ includes other arithmetic operators in addition to the equal sign.

O perator Example Meaning-------------------------------------------- -------------------------= i Num1 = i Num2+= i Num1 += i Num2 i Num1 = i Num1 + i Num2-= i Num1 -= i Num2 i Num1 = i Num1 - i Num2*= i Num1 *= i Num2 i Num1 = i Num1 * i Num2/= i Num1 /= i Num2 i Num1 = i Num1 / i Num2

%= i Num1 %= i Num2 i Num1 = i Num1 % i Num2

Assignment statements such as sum += 10 or its equivalent, sum =sum + 10, are very common in programming.

Incr eme ntal and d ecr eme ntal op erators

O perator Description---------------------------------------------------------------


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++ I ncrease an operand by a value of one-- Decrease an operand by a value of one

The increment (++) and decrement (--) unary operators can be usedas prefix or postfix operators to increase or decrease value.

y A pr e fix operator is placed before a variable and returns thevalue of the operand after the operation is performed.

y A postfix operator is placed after a variable and returns thevalue of the operand before the operation is performed.

Prefix and postfix operators have different effects when used in astatement

b = ++a;will first increase the value of a to 6, and then assign that new valueto b. I t is equivalent to

a = a +1; b = a;

On the other hand, execution of the statement b = a++;

will first assign the value of 5 to b, and then increase the value of ato 6. I t is now equivalent to

b = a;a = a + 1;

The decrement operators are used in a similar way.

3.2 FORMATTING NUMBER FOR PROGRAM OUTPUT3.2.1 Stream ManipulatorsS tream manip u lator functions are special stream functions thatchange certain characteristics of the input and output.


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The main advantage of using manipulator functions is they facilitatethe formatting of the input and output streams.

y setw() : stands for set width . This manipulator is used to specifythe minimum number of the character positions on the outputfield a variable will consume.

y setpr ecision() : is used to control the number of digits of anoutput stream display of a floating point value. S etprecision (2) means 2 digits of precision to the right of the decimal point.

# include int main(){

cout


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o setiosflags ( ios::fi xed ) means the output field will useconventional fixed-point decimal notation.

o setiosflag ( ios::showpoint ) means the output field will showthe decimal point for floating point number.

o setiosflags ( ios::scientific ) means the output field will use

exponential notation.Example:cout


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// a progran to illustrate output conversions# include # include void main(){

cout


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The output of the above program:The decimal value of 025 is 21The decimal value of 0x37 is 55

3.3 USING MATHEMATICAL LIBRARY FUNCTIONS

I f your program uses mathematic function sqrt () , it should have the preprocessor command # includ e< m ath.h> in the beginning of the program. This makes a mathematical library accessible.

Function Name Description R eturn Value-----------------------------------------------------------------abs(a) A bsolute value Same data type as argumentlog(a) Natural logarithm doublesin(a) sine of a (a in radians) doublecos(a) cosine of a (a in radians) doubletan(a) tangent of a (a in radians) doublelog10(a) common log (base 10) of a double

pow(a1,a2) a1 raised to the a2 power doubleexp(a) e a doublesqrt(a) square root of a double

Table 3.2 Some mathematical built-in functionsExcept abs ( a ) , they all take an argument of type do u ble and return avalue of type do u ble .Example 3.3.1# include


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int height;double time;height = 800;time = sqrt(2 * height / 32.2); // gravitational constant g =

32.32cout


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3.4 PROGRAM INPUT USING THE cin OBJECT

3.4.1 Standard Input StreamThe cin object reads in information from the keyboard via thestandard input stream.The e xtraction op erator (>>) retrieves information from the inputstream.# include void main(){

float num1, num2, product;cout > num1;cout > num2;product = num1 * num2;cout


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cout > num1 >> num2 >> num3;average = (num1 + num2 + num3) / 3.0;cout


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total = amount + taxes;cout


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The strcat () function combines two strings using the syntax:strcat(d estination, sourc e );

The functions listed in Table 3.3 are contained in the string.h header file. To use the functions, you must add the statement# incl u de to your program.

# include # include

int main( void )

{char string[80];strcpy( string, "Hello world from " );strcat( string, "strcpy " );strcat( string, "and " );strcat( string, "strcat!" );

printf( "String = %s\n", string );}Output:String = Hello world from strcpy and strcat!

# include # include char string1[] = "The quick brown dog jumps over the lazyfox";char string2[] = "The QUICK brown dog jumps over the lazyfox";


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int main( void ){

char tmp[20];int result;/* Case sensitive */printf( "Compare strings:\n %s\n %s\n\n", string1, string2

);result = strcmp( string1, string2 );if( result > 0 )

strcpy( tmp, "greater than" );

else if( result < 0 )strcpy( tmp, "less than" );else

strcpy( tmp, "equal to" );printf( " strcmp: String 1 is %s string 2\n", tmp );/* Case insensitive (could use equivalent _stricmp) */result = _stricmp( string1, string2 );if( result > 0 )

strcpy( tmp, "greater than" );else if( result < 0 )

strcpy( tmp, "less than" );else

strcpy( tmp, "equal to" );printf( " _stricmp: String 1 is %s string 2\n", tmp );

}Output:Compare strings:


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The quick brown dog jumps over the lazy foxThe QUICK brown dog jumps over the lazy foxstrcmp: String 1 is greater than string 2

_stricmp: String 1 is equal to string 2


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Chapter 4 SELECTION STRUCTURE

The flow of control refers to the order in which a programsstatements are executed. The nor m al flow of control for all

programs is seq uential . S el ection , r e petition and function in vocation structures permit theflow of control to be altered in a defined way.

4.1 SELECTION CRITERIA

C om parison O perators

Comparison operators are used to compare two operands for

equality and to determine if one numeric value is greater thananother.

O perator Description---------------------------------------------------= = equal!= not equal

> greater than< less than= greater than or equal

Example:a = = b (a*b) != cs == y x


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Logical O peratorsLogical operators are used for creating more complex conditions.

O perator Description---------------------------------------------------&& AN D|| OR ! NOT

Example:(age > 40) && (term < 10)(age > 40) || (term < 10)

!(age > 40)( i==j) || (a < b) || complete

4.2 THE if-else STATEMENTThe syntax for an if .. else statement:if (conditional expression) {

statements;}else {

statements;}


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Figure 4.1 The flow chart of if-else statement

Example 4.2.1# include # include

const float LOWRATE = 0.02; // lower tax rateconst float HIGHRATE = 0.025; // higher tax rate

const float CUTOFF = 20000.0; // cut off for low rateconst float FIXEDAMT = 400; // fixed dollar amount for higher rate amountsint main(){

float taxable, taxes;cout > taxable;if (taxable


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// set output formatcout


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cout


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Figure 4.2 The flow chart of one-way if statement

Example 4.2.3# include int main(){

const float LIMIT = 3000.0;int idNum;

float miles;cout > idNum >> miles;if(miles > LIMIT)

cout


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Th e if- else C hain

When an if statement is included in the else part of an existing if statement, we have an if-else chain .Example 4.3.1# include int main(){

char marcode;cout > marcode;if (marcode == 'M')

cout


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{float monthlySales, income;cout > monthlySales;if (monthlySales >= 50000.00)

income = 375.00 + .16 * monthlySales;else if (monthlySales >= 40000.00)




income = 250.00 + .05 * monthlySales;else

income = 200.00 + .03 * monthlySales;// set output format

cout


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4.4 THE switch STATEMENTThe switch statement controls program flow by executing a set of statements depending on the value of an expression. Note: The valu e of e xpr ession must be an int e g er data typ e, whichincludes the char, int , long int , and short data types.

switch(expression){case label:

statement(s);break;

case label;statement(s);

break;default:

statement(s);}

y What about bool data type???y The break statement causes an immediate exit from the switch

statement.y What happens if the break statements are omitted???

# include int main()


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{int opselect;double fnum, snum;cout > fnum >> snum;cout


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Please type in two numbers: 12 3Enter a select code:

1 for addition2 for multiplication3 for division : 2

The product of the numbers entered is 364.5 CONDITIONAL EXPRESSIONSProvide an alternative way of expression a simple if-else statement.

e xpr ession1 ? e xpr ession2 : e xpr ession3I f the value of e x pression1 is nonzero (true), e x presson 2 isevaluated; otherwise, e x pression3 is evaluated.The value for the complete conditional expression???Example: The if statement:

if (hours > 40)rate = 0.45else

rate = 0.02;can be replaced with:

rate = (hours > 40) ? 0.45 : 0.02;

4.6 THE enum SPECIFIER The enu m specifier create an enumerated data type.Example:

enu m day { m on, tu e , w ed, thr, fri, sat, sun} ;

enu m color {r ed, gr ee n, y ellow}; Any variable declared to be of type color can take only a value of red or green or yellow . S imiliarly for type day .


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The statementenum day a, b,c;

declares the variables a, b , and c to be of type day .# include void main(){

enum color{red, green, yellow};enum color crayon = red;cout


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Chapter 5 REPITITION STRUCTURES

5.1 INTRODUCTIONC++ provides three different forms of repetition structures:

y while structurey for structurey do-while structure

Each of these structures requires a condition that must be evaluated.y at the beginning of the loop: pre-test loop or entrance-controlled

loop.y at the end of the loop: post-test loop or exit-controlled-loop.

5.2 while LOOPSThe while statement is used for repeating a statement or series of statements as long as a given conditional expression is evaluated totrue.while( condition expression){

statements;}Example 5.2.1# include void main(){

int count;count = 1; // initialize countwhile (count


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}}The output of the above program:1 2 3 4 5 6 7 8 9 10

Figure 5.1 The flow chart of the while statement# include void main()

{int i;i = 10;while (i >= 1){

cout


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5.3 INTERACTIVE while LOOPCombining interactive data entry with the repetition capabilities of the while statement produces very adaptable and powerful programs.# include # include void main(){

const int MAXNUMS = 4;int count;float num;cout


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The number entered is 5.000Enter a number: 103.456The number entered is 103.456Enter a number: 1267.89The number entered is 1267.890

S entin elsI n programming, data values used to indicate either the start or endof a data series are called sentinels .Example 5.3.2# include

const int HIGHGRADE = 100;void main(){

float grade, total;grade = 0;total = 0;cout


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br eak stat eme nt The break statement causes an exit from the inn er m ost enclosingloop statement. while( count num;if (num > 76){

cout 100)


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continue;total = total + grade;count++;

}

Th e null stat eme nt

A semicolon with nothing preceding it is also a valid statement,called the nu ll statement .if (a > 0)

b = 7;else ;

5.4 for LOOPSy The for statement is used for repeating a statement or series of

statements as long as a given conditional expression evaluatesto true.

y Main differences between while statement and for statement:included code in the for statement:

o

to initialize a counter variable ando changes its value with each iteration

for ( initialization expression; condition; update statement){statement(s);

}Example 5.4.1


int count;for (count = 2; count


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cout


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cout


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for(j = 1; j


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do {cout> idNum;

} while (idNum < 1000|| idNum> 1999);Here, a request for a new id-number is repeated until a valid number is entered.

do {cout> idNum;if (idNum < 1000 || idNum > 1999)

{cout


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else break;} while (true);

5.7 STRUCTURED PROGRAMMING WITH C++

Th e goto S tat eme nt (khong n en dung goto)

I n C++, goto statement an unconditional branch, is just a legacycode from C language. The result of the goto statement is a changein the flow of control of the program to the first statement after thela be l specified in the goto statement.

start: // labelif (count > 10) go to end;

go to start;end: cout


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y The sequence structure is built into C++.y C++ provides three types of selection structures:

o - if statement (single-selection structure)o - if-else statement (double-selection structure)o

- switch statement. (multiple-selection structure)y C++ provides three types of repetition structures:o - while statemento - do-while statemento - for statement

y We will see that each control structure has only one entry point

and one e xit point . These single-entry / single-e xit control str u ct u res make it easy to build programs.

y One way to build program is to connect the exit point of onecontrol structure to the entry point of the next. This way iscalled control-str u ct u re-stacking .

y Another way is to place one control structure inside another control structure. This way is called control-str u ct u re-nesting .

y Consistent applying reasonable indentation conventionsthroughout your programs greatly improves programreadability. We suggest a fixed-size three blanks per indent.

y Using good control structures to build programs is one of themain principles of structured programming. Another principleof structured programming is top-down, stepwise refinement .

Top-down, S t e pwis e R e fin eme nt

Consider the following problem:Develop a class-averaging program that will process an

arbitrary number of grades each time the program is run.


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First R efinement: Initialize variables

Inp u t, s u m and co u nt the e xam grades

Calc u late and print the class a verage

Second R efinement: Inp u t the first gradeW hile the u ser has not as yet entered the sentinel

Add this grade into the running total A dd one to the grade co u nter

Inp u t the ne xt grade

Calc u late and print the class a verage Third R efinement:

Initialize total to zero Initialize co u nter to zero

Inp u t the first grade W hile the u ser has not as yet entered the sentinel

A dd this grade into the r u nning total A dd one to the grade co u nter

Inp u t the ne xt grade

If the co u nter is not eq u al to zero

set the a verage to the total di vided by the co u nter

print the a verageelse

Print No grades were entered.

Final step: We come to the following C++ program.# include


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int total, // sum of gradesgradeCounter, // number of grades enteredgrade; // one grade

double average; // number with decimal point for average

// initialization phasetotal = 0;gradeCounter = 0;

// processing phasecout > grade;while ( grade != -1 ) {

total = total + grade;

gradeCounter = gradeCounter + 1;cout > grade;

}// termination phaseif ( gradeCounter != 0 ) {

average = double ( total ) / gradeCounter;cout


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cout


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}The output is:

AB

CDF

# include int main()

{const int MAXGRADES = 5;int i, grade[MAXGRADES], total = 0;cout grade[i];

}

cout


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return 0;}

5.8.2 Multi-Dimensional Arraysy The C++ language allows arrays of any type, including arrays

of arrays.int a[1000]; // a one-dimensional arrayint b[3][5]; // a two-dimensional arrayint c[7][9][2]; // a three-dimensional arrayI n these above example, b has 3 v 5 elements, and c has 7 v 9 v 2elements. Starting at the base address of the array, all the array

elements are stored contig u

ou sly in memory.y For the array b, we can think of the array elements arranged as

follows:col 1 col2 col3 col4 col5

row 1 b[0][0] b[0][1] b[0][2] b[0][3]b[0][4]

row 2 b[1][0] b[1][1] b[1][2] b[1][3]b[1][4]

row 3 b[2][0] b[2][1] b[2][2] b[2][3]b[2][4]

Example 5.8.3This program checks if a matrix is symmetric or not.# include# includeconst int N = 3;void main( ){


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int i, j;int a[N][N];bool symmetr = true;for ( i=0, i< N, ++i)

for (j=0, j> a[i][j];

for ( i=0, i< N, ++i)for (j=0, j


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struct employee{char* firstname;char* lastname;long salary;

};W her e we d e fin e a structur e in our progra m ???To access the field inside a structure variable, you append a periodto the variable name, followed by the field name using the syntax:

varia bl e .fi eld ;

When you use a period to access a structure fields, the period isreferred to as the membe r s el ection op erator . Example 5.9.1# include struct Date // this is a global declaration{

int month;int day;

int year;};void main(){

Date birth;birth.month = 12;

birth.day = 28;birth.year = 1982;cout


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{ 35987, "Ernst, T.", 5.43 },{ 36203, "Gwodz, K.", 8.72 } };

cout


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Chapter 6 MODULARITY USING FUNCTIONS

6.1 FUNCTION AND PARAMETER DECLARATIONSA function allows you to treat a r elat ed group of C++ statements as

a single unit. De fining a Functiondata_type name_of_function (parameters){

statements;}A function definition consists of four parts:

y A reserved word indicating the return data type of the functionsreturn value.

y The function namey Any parameters required by the function, contained within

parentheses.y The functions statements enclosed in curly braces { }.

void FindMax(int x, int y) /noi dung cua mot ham{

int maxnum;if ( x > = y)

maxnum = x;else

maxnum = y;cout


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You designate a data type for function since it is common to return avalue from a function after it executes. Variable names that will be used in the function header line arecalled for m al para me t ers .(noi dung tham so)

C all Functions

To execute a function, you must invoke, or call it from the main () function.The values or variables that you place within the parentheses of afunction call statement //cau lenh// are called arguments or actual

para me t ers .Example: findMax( firstnum, secnum);

Function P rototyp es(ha m nguy en)A function prototype d eclar es to the compiler that you intend to usea function later in the program.I f you try to call a function at any point in the program prior to itsfunction prototype or function definition, you will receive an error when you compile the project.Example 6.1.1void FindMax(int, int) ; // the function prototypeint main() //function father {

function header line

{named constants;

variable declarations;any other statements

}

Function header

Function body


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int firstnum, secnum;cout > firstnum;cout > secnum;FindMax(firstnum, secnum); // the function is called herereturn 0;

}

P assing b y V alu e y The called function receives a copy of the values stored in the

actual parametersy Control is transferred to the called function.

Example: The statement find M a x( firstn u m, secn u m ); calls thefunction find M a x() and causes the values currently residing in thevariables firstn u m and secn u m to be passed to findMax().// ham co 2gia tri can dinh nghia(theo mot bien nao do.example:int

Functions with E m pty P ara me t er ListsThe function prototype requires either the keyword void or nothingat all between the parentheses following the function name.Example:

int display(); list in parenthesesint display(void); list:void

6.2 RETURNING VALUES //dieu chinh tri lai for variable To actually return a value to a variable, you must include the returnstatement within the called function.

r eturn valu e; or r eturn( valu e );


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R emember that valu es passes back and forth between functions must be of the sa me data typ e.Example 6.2.1# include int FindMax(int, int); // the function prototypeint main(){

int firstnum, secnum, max;cout > firstnum;cout > secnum;max = FindMax(firstnum, secnum); // the function is called

herecout


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# include double tempvert(double); // function prototypeint main(){

const CONVERTS = 4; // number of conversions to be madeint count; // start of declarationsdouble fahren;for(count = 1; count fahren;

cout


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# include inline double tempvert(double inTemp) // an inline function{

return (5.0/9.0) * (inTemp - 32.0);}int main(){

const CONVERTS = 4; // number of conversions to bemade

int count; // start of declarationsdouble fahren;

for(count = 1; count fahren;cout


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void showabs(int x){

if( x < 0)x = -x;cout


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6.3 VARIABLE SCOPE //tam vuc cua bien Scope refers to wh er e in your program a declared variable or constant is allow ed us ed .

V aria bl e scop e y G lobal scop e refers to variables declared outside of any

functions or classes and that are available to all parts of your program.

y Local scop e refers to a variable declared inside a function andthat is available only within the function in which it is declared.

Example 6.3.1# include int firstnum; // create a global variable named firstnumvoid valfun(); // function prototype (declaration)int main(){

int secnum; // create a local variable named secnumfirstnum = 10; // store a value into the global variable

secnum = 20; // store a value into the local variablecout


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{int secnum; // create a second local variable named secnumsecnum = 30 ; // this only affects this local variable's valuecout


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{float number = 26.4; // a local variable named number

//ten bien dia phuongcout


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extern float price;extern float yld;

6.4.1 Local Variable Storage Classes //bien dia Phuong cat giulop

Local variables can only be members of the auto, static, or register storage classes.I f no class description is included in the declaration statement, thevariable is automatically assigned to the auto class. neu khong co lop

bao gom cac lenh khai bao thi mac dinh bien tu dong se gan 1 lop.

A uto m atic V aria bl esy A uto m atic storag e duration refers to variables that exists only

during the lif eti me of the co mm and block (such as a function)that contains them.

Example 6.4.1# include void testauto(); // function prototypeint main(){

int count; // count is a local auto variablefor(count = 1; count


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cout


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teststat(); return 0;

}void teststat(){

static int num = 0; // num is a local static variablecout


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register double difference;

6.4.2 Global Variable Storage Classes //lop:bien toan cuc y Created by definition statements e xternal to any function. sang

tao bang cau dinh nghia cau lenhexternaly Exists until the program in which it is declared finishesexecuting.

y Global variables may be declared as static or e xternal (but not both).

y The purpose of the e xt ernal storage class is to e xt end th e scop e of a glo bal varia bl e beyond its normal boundaries.

//file1int price;float yield;static double coupon;..int main(){

func1():func2():func3():func4():

}

int func1();{

.

.}


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int func2();{

.

.}//end of file1

//file2double interest;int func3();{

.

.}int func4();{

.

.}//end of file2

y A lthough the variable price has been declared in file1 , we wantto use it in file2. Placing the statement e xtern int price in file2,we can extend the scope of the variable price into file2.//khai

bao bien pricexac dinh tam vuc cua no trong file2 y Now the scope of the variable price is not only in file1 , but also

in f u nc3 and f u nc4 . bay gio gia tri cua bien khong con o trongfile1ma con trong cac file2.3


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//file1int price; //price : gia trifloat yield; //yield : loi nhuanstatic double coupon; //coupon : phieu (mua hang)..int main(){

func1():func2():func3():

func4():}external double interest;int func1();{

.

.}int func2();{

.

.}//end of file1

//file2double interest;


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external int price;int func3();{

.

.}int func4();{

extern float yield;..

}//end of file2 Note:1. We cannot make static variables external.2. The scope of a global static variable cannot extend beyond the

file in which it is declared. static gia tri tinh khong thay doi.xettrong ham nay thi bien dung cho rat nhieu file khac nhau nenkhong the dat truoc valiable static//no o dang congkhai//xac nhan la toan cuc.

6.5 PASS BY REFERENCE USING REFERENCEPARAMETERS //tham chieu den 1 tham so da co

R e f er enc e P ara me t ersy call b y valu e, a copy of the arguments value is made and passed to the called function. Changes to the copy do not effectthe original variables value in the caller.

y call- b y-r e f er enc e, the caller gives the called function the abilityto access the callers data directly, and to modify that data if thecalled function chooses so.


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For example, the declaration int& count in the function h ead er means count is a reference parameter to an int.Example 6.5.1# include void newval(float &, float&); // prototype with tworeferences //kieu mau voi 2 bien tham khaoint main(){

float firstnum, secnum;cout > firstnum >> secnum;

cout


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The output of the above program:Enter two numbers: 22.5 33.0

The value in firstnum is: 22.5The value in secnum is: 33

The value in xnum is: 22.5The value in ynum is: 33

The value in firstnum is: 89.5

The value in secnum is: 99.5

Example 6.5.2# include void calc (float, float, float, float&, float&); // prototypeint main(){

float firstnum, secnum, thirdnum, sum, product;cout > firstnum >> secnum >> thirdnum;calc(firstnum, secnum, thirdnum, sum, product); / call the

functioncout


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result = factorial(n);cout


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The activation-record for the first call to factorial().

The stack for the second call to factorial

The stack for the third call to factorial()Example 6.6.2

1

reserved for returnvalue

return address

2

reserved for returnvalue

return address

3

reverved for returnvalue

return address

2

reserved forreturn value

return address

3

reserved forreturn value

return address


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Fibonacci numbers:

F N = F N-1 + F N-2 for Nu 2F0 = F 1 = 1

# includeint fibonacci(int);void main(){

int m;cout m;cout


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modify A rray( hourly Temperature , size);//modify thay doiham,bo sung ham.

passes the array ho u rlyTemperat u re and its size to functionmodify A rray .

void modifyArray(int b[], int arraySize)

Example 6.7.1To illustrate the use of array and function, we set for ourselves thefollowing tasks:

1. R ead in the amount to be deposited in the bank, the interest rateand the number of years to deposit.

2. I nvoke the function to compute a table which keeps the amountwe get after i years of deposit at the i-th component of the array.

3. Display out the above array/* Compute compound interest */# include# include# define YMAX 50void interest(double, double, int, double []);void main(){

double deposit, rate;int i, years;

double compounded[YMAX];cout>deposit>>rate>>years;cout


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or equal


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a[x] = 2*x;cout searchKey;element = linearSearch(a, searchKey, arraySize);if(element !=-1)

cout


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dou ble dPrimeInterest ;

dou ble * pPrimeInterest ;

pPrimeInterest = & dPrimeInterest ; y To access or modify the contents of the variable pointer to by

the pointer, you precede a pointer name in an expression withthe de-reference (*) operator .

Example 6.8.1The program in this example demonstrates the pointer operators.Memory locations are output in this example as hexadecimalintegers.

# includevoid main(){

int a;int *aPtr; // aPtr is a pointer to an integer a = 7;

aPtr = &a; //aPtr set to address of acout


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The value of a is 7The value of *aPtr is 7

6.8.1 Pointers and Arrays Notice that the name of an array by itself is equivalent to the bas e addr ess of that array. that is, the name z in isolation is eq u ivalent tothe e x pression & z[0] .Example 6.8.2a# includevoid main(){ int z[] = { 1, 2, 3, 4, 5};

cout


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The following program displays all elements in an array. I t uses pointer and offset to access to each element in the array.

# include int main(){

const int ARRAYSIZE = 5;int *gPtr; // declare a pointer to an int

int i, grade[ARRAYSIZE] = {98, 87, 92, 79, 85};gPtr = &grade[0];

// store the starting array addressfor (i = 0; i < ARRAYSIZE; i++)

cout


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6.8.2 Pointers and StringsWe can scan through a string by using pointer.

/* Printing a string one character at a time using a non-constant pointer to constant data */# includevoid main( ){

char string[] = Adams;char *sPtr;

sPtr = &string[0];cout


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struct Employee // declare a global type{

int idNum;double payRate;double hours;

};double calcNet(Employee); // function prototypeint main(){

Employee emp = {6782, 8.93, 40.5};double netPay;

netPay = calcNet(emp); // pass by valuecout


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y An alternative to the pass-by-value function call, we can pass astructure by passing a pointer . The following example showshow to pass a structure by passing a pointer.

# include struct Employee // declare a global type{

int idNum;double payRate;double hours;

};double calcNet(Employee *); //function prototypeint main(){

Employee emp = {6782, 8.93, 40.5};double netPay;

netPay = calcNet(&emp); // pass an addresscout


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The net pay for employee 6782 is $361.665

y Is th er e any oth er solutions???

6.10 THE typedef DECLARATION STATEMENT

Construct alternate names for an existing C++ data type name.typed e f data-typ e new-typ e-na me

Example:typedef float REAL;REAL val; float val;

Example:typedef double* DPTR;DPTR pointer1; double* pointer1;

Example:typedef struct{

char name[20];int idNum;

} EMPREC;The declaration

EMPREC employee[75];is equivalent to

struct{

char name[20];int idNum;


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} employee[75];


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Chapter 7 INTRODUCTION TO CLASSES

7.1 STACK VERSUS HEAP //ngan truy cap den 1 vung du lieuma minh da gioi han

y A stack is a region of memory where applications can store datasuch as local variables, function calls, and parameter information. //ngan xep la mot mien cua bon ho noi ma ungdung co the cat giu du lieu nhu la mot bien dia Phuong, goiham,thong tin tham so.

y The programmers have no control over the stack. C++automatically handles placing and removing data to and from

stack.y The heap or free store, is an area of memory that is available to

application for storing data whose existence and size are notknown until run-time.

Th e new K e yword The new keyword creates a variable on the heap and returns a

pointer to the variables heap address. //tu khoa NEW tao ra 1 bientrong 1 vung du lieu nao do.sau do con tro se tra 1 bien trong vungdu lieu theo mot dia chi da xac dinh.

new type_name ;

Example:int * pPointer;

pPointer = new int; Th e d el et e K e yword

You use the delete keyword to de-allocate memory that has beenreserved on the heap.

delete pointer_name ;


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delete pPointer;int *arrayPtr = new int[10];delete [] arrayPtr;

Notice that the delete keyword does not delete the pointer itself. R ather, it deletes the contents of the heap memory address pointed to

by a pointer variable. You can reuse(dung lai) the pointer itself after calling the delete keyword. The pointer still exists and points tothe same heap memory address that it did before calling the delete

keyword.Example 7.1.1# includevoid main( ){

double* pPrimeInterest = new double;

*pPrimeInterest = 0.065;cout


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}The output of the above program:The value of pPrimeInterest is: 0.065The memory address of pPrimeInterest is: 0x0066FD74

The value of pPrimeInterest is: 0.070The memory address of pPrimeInterest is: 0x0066FD74. Note: The above program declares the pPrimeInterest pointer on the

heap and assign to it a value of 0.065. Then the delete keyworddeletes the heap address that stores the value of 0.065. Finally, anew value is added to the heap address. You can see that after the delete statement executes, the pPimeInterest pointer still

point to the same memory address.Example 7.1.2:The following program allocates contiguous memory for an array of integers using the new operator and the object of the array isdestroyed by the delete operator. The program reads a set of numbers from keyboard and displays it on the screen.

# include void main( ){

int *ptr_a = new int[20];int *ptr_n = new int;int i;cout > *ptr_n;for (i = 0; i ptr_a[i];


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}cout


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y Classes are referred to as us er-d e fin ed data typ es or programmer-defined data types because you can work with aclass as a single unit, or objects, in the same way you work withvariables.

y When you declare an object from a class, you are said to be

instantiating an object.y The most important feature of C++ programming is class

definition with the class keyword. You define classes the sameway you define structures, and you access a classs datamembers using the member selection operator .

Example:

class Stocks //ton tai dau; sau khi ket thuc class{public:

int iNumShares;double dPurchasePricePerShare;

double dCurrentPricePerShare;}; void main( ){

Stocks stockValue;stockValue.iNumShares = 500;stockValue.dPurchasePricePerShare = 10.785;

stockValue.dCurrentPricePerShar = 6.5;}


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P oint ers and R e f er enc es to Obje ctsy When declaring and using pointers and references to class

objects, follow the same rules as you would when declaring andusing pointers and references to structures.

y You use the indirect member selection operator (->) to accessclass members through a pointer to an object either on stack or on the heap.

Example 7.2.1//stock : kho chua cac du lieu lien quan den ham# includeclass Stocks{public:

int iNumShares;

double dPurchasePricePerShare;double dCurrentPricePerShare;

};double totalValue(Stocks* pCurStock);void main( ){

//allocated on the stack//with a pointer to the stack objectStocks stockPick;Stocks* pStackStock = &stockPick;pStackStock->iNumShares = 500;

pStackStock-> dPurchasePricePerShare = 10.785;pStackStock-> dCurrentPricePerShare = 6.5;cout dPurchasePricePerShare = 32.5;pHeapStock-> dCurrentPricePerShare = 48.25;cout iNumShares;return dTotalValue;

}


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Output of the above program:32509650 Note: The totalVal u e() function is not a function member of theStocks class. R ather, it is a function that is available to the entire

program.7.3 INFORMATION HIDING

y The principle of information hiding states that any classmembers that other programmers , or clients, do not need toaccess or know about should be hidden.

y Many programmers prefer to make all of their data member

private in order to prevent clients from accidentally assigning the wrong value to a variable or from viewing the internalworkings of their programs.

7.3.1 Access SpecifiersAccess specifiers control a clients access to data members andmember functions. There are four levels of access specifiers: public,

private, protected, and friend.y The public access specifier allows anyone to call a classs

function member or to modify a data member.y The private access specifier is one of the key elements in

formation hiding since it prevents clients from calling member functions or accessing data members.

y Both public and private specifiers have what is called classscope : class members of both access types are accessible by anyof a classs member functions.


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Example 1:class Stocks {public:


private:double dCurrentPricePerShare;

};

Example 2:

class Times {public:Times();void setTime( int, int, int );void printMilitary();void printStandard();

private:int hour;int minute;int second;

};

Stocks

i NumSharesdPurchasePricePer SharedCurrentPricePer Share


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y The d e fault acc ess specifier for classes is pri vat e.

7.3.2 Interface and Implementation FilesThe separation of classes into separate interface and implementationfiles is considered to be a f u ndamental software de velopment techniq u e since it allows you to hide the details of how your classesare written and makes it easier to modify programs.

y The interface code refers to the data member and functionmember declarations inside a classs braces.

y The implementation code refers to a classs functiondefinitions and any code that assigns values to a classs datamembers.

P r eve nting M ultipl e Inclusion

With large program, you need to ensure that you do not include

multiple instances of the same header file.C++ generates an error if you attempt to compile a program thatincludes multiple instances of the same header file. To prevent thiskind of error, most C++ programmers use the # define preprocessor directive with the # if and # endif preprocessor directives in header files.

Times

hour minute

second

setT ime() printMilitary pring Standard()


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The # if and # endif preprocessor directives determine which portionsof a file to compile depending on the result of a conditionalexpression.The syntax for the # if and # endif preprocessor directives:

# if conditional e

x pression statements to compile ;

# endif Example:# if !defined(STOCKS_H)# define STOCKS_Hclass Stocks {private:

int iNumShares;double dPurchasePricePerShare;double dCurrentPricePerShare;

};# endif Note: Common pratice when defining a header files constant is touse the header files name in uppercase letters appended with H. For example, the constant for the stocks.h header is usually defined asSTO CK S _H.

7.4 MEMBER FUNCTIONSA lthough member functions are usually defined in animplementation file, they can also be defined in an interface file.Functions defined inside the class body in an interface file are calledinline functions .Example:class Stocks {


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public:double getTotalValue(int iShares, double dCurPrice){

double dCurrentValue;iNumShares = iShares;dCurrentPricePerShare = dCurPrice;dCurrentValue = iNumShares*dCurrentPricePerShare;return dCurrentValue;

}private:


double dCurrentPricePerShare;};

Example 7.4.1//stocks.hclass Stocks{public:

double getTotalValue(int iShares, double dCurPrice);private:

Stocks

i N

umS

haresdPurchasePricePer SharedCurrentPricePer Share

getTotalValue()


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int iNumShares;double dPurchasePricePerShare;double dCurrentPricePerShare;

};# endif

// stocks.cpp# include stocks.h# include

double Stocks::getTotalValue(int iShares, double dCurPrice){

double dCurrentValue;iNumShares = iShares;dCurrentPricePerShare = dCurPrice;dCurrentValue = iNumShares*dCurrentPricePerShare;return dCurrentValue;

}void main(){

Stocks stockPick;cout


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{function body

}Example 7.4.2// time1.h# if !defined(TIME1_H)# define TIME1_Hclass Time {public:

Time(); // constructor void setTime( int, int, int ); // set hour, minute, secondvoid printMilitary(); // print military time formatvoid printStandard(); // print standard time format

private:int hour;int minute;int second;

};// Time1.cpp# include time1.h# include

// Time constructor initializes each data member to zero.

// Ensures all Time objects start in a consistent state.Time::Time() {hour = minute = second = 0;}


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void Time::setTime( int h, int m, int s ){

hour = ( h >= 0 && h < 24 ) ? h : 0;minute = ( m >= 0 && m < 60 ) ? m : 0;second = ( s >= 0 && s < 60 ) ? s : 0;

}

void Time::printMilitary(){

cout


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t.setTime( 13, 27, 6 );cout


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C onstructor Functionsy A constructor function is a special function with the same

name as its class. This function is called automatically when anobject from a class is instantiated.

y You define and declare constructor functions the same way youdefine other functions, although you do not include a returntype since constructor functions do not return values.

Example:

class Payroll{public:

Payroll( ){ // constructor functiondFedTax = 0.28;dStateTax = 0.05;

};private:

double dFedTax;double dStateTax;

}y You also include just a function prototype in the interface file

for the constructor function and then create the functiondefinition in the implementation file.

Payroll::Payroll( ){ // constructor functiondFedTax = 0.28;dStateTax = 0.05;

};Example 7.4.3# include


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# include

// class declaration sectionclass Date{

private:int month;int day;int year;

public:Date(int = 7, int = 4, int = 2001); // constructor with default

values};

// implementation sectionDate::Date(int mm, int dd, int yyyy){

month = mm;day = dd;year = yyyy;cout


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return 0;}The output of the above program:Created a new data object with data values 7, 4, 2001Created a new data object with data values 7, 4, 2001Created a new data object with data values 4,1, 2001

y De fault constructor refers to any constructor that does notrequire any parameters when it is called.

For example in Example 7.4.3, the prototype Date ( int = 7, int = 4,int = 2001 ) is valid for a default constructor. Here, each argumenthas been given a default value. Then an object can be declared astype Date without supplying any further arguments.

A ssign me nts

1. R ead the following program for understanding. Then edit it as one program file and run it on V isual C++ environment.# includeclass student{private:

long int rollno;int age;char sex;float height;

float weight;public:

void getinfo();void disinfo();

};


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void student::getinfo(){

cout > rollno;cout > age;cout > sex;cout > height;cout > weight;}void student::disinfo(){

cout


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}Then organize the program into one interface file and oneimplementation file and run them again.2. R ead the following program that reads the students informationfrom the keyboard and displays the contents of the whole class onthe screen//assign4_2.cpp# includeconst int MAX = 100class student{private:

long int rollno;int age;char sex;float height;float weight;

public:

void getinfo();void disinfo();};void student::getinfo(){

cout > rollno;cout > age;cout > sex;cout


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cin >> height;cout > weight;

}void student::disinfo(){

cout


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I mplement the above program on V isual C++ environment.3. The following program simulates a simple banking system inwhich the initial balance and the rate of interest are read from thekeyboard and these values are initialized using the constructor function. The program consists of the following methods:

y to initialize the balance amount and the rate of interesty to make a deposity to withdraw an amount from the balancey to find the compound interest based on the rate of interesty to know the balance amounty to display the menu options//demonstration of constructor

//simulation of simple banking system# include# includeclass account{private:

float balance;float rate;

public:account(); //constructor void deposit();void withdraw();void compound();void getbalance();void menu();

};account::acount()


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{cout> balance;cout> rate;

}//depositvoid account:: deposit(){

float amount;cout amount;

balance = balance + amount;}void account::withdraw(){

float amount;cout amount;

if(amount


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balance = balance + interest;cout


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break;case 'd':

acct.compound();break;

case 'd':acct.getbalance();break;}

}}I mplement the above program on V isual C++ environment.

4. The following program solves a quadratic equation using anobject-oriented programming technique in which the member functions are defined as an inline substitution.

(chuong trinh bac hai sau day se lam sang to ,su dung viec dinhhuong doi tuong trong chuong trinh bang thu thuat ma so hamdinh nghia ro tinh chat nhu mot su thay the ben trong)

#include# include

class equation{private:

float a;float b;float c;

public:void getinfo(float a, float b, float c);void display( );void equal(float a, float b);void imag( );


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void real(float a, float b, float det);}; // end of class declaration section// beginning of implementation sectionvoid equation::getinfo(float aa, float bb, float cc){

a = aa; b = bb; c = cc;}void equation::display( ){

cout


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cout


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Note: I n the above program, the class declaration section and classimplementation section are included in the same source file (.cppfile).5. Construct a class name S t u dent consisting of an integer studentidenfification number, an array of five floating point grades, and an

integer representing the total number of grades entered. Theconstructor for this class should initialize all S tudent data membersto zero. I ncluded in the class should be member functions to

- enter a student I D number,- enter a single test grade and update the total number of grades

entered, and- compute an average grade and display the student I D following

by the average grade.I nclude the class S t u dent within a complete program. The programshould declare two objects of type Student and accept and displaydata for the two objects to verify operation fo the member functions.6. Construct a class named Rectangle that has floating-point datamembers name length and width . The class should have a

constructor that sets each data member to 0, member functionsnamed perimeter () and area () to calculate the perimeter and area of a rectangle, respectively, a member function named getdata () to seta rectangles length and width, and a member function named

showdata () that display a rectangles length, width, perimeter, andarea.I nclude the Rectangle class within a working C++ program.


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Chapter 8 OBJECT MANIPULATION

8.1 ADVANCED CONSTRUCTORS// xay dung dang cao cap I n the last chapter, we already notice that constructors can provide a

mechanism for initializing data members. However, constructors cando more than initializing data members. They can execute member functions and perform other type of initialization routines that aclass may require when it first starts.

8.1.1 Parameterized Constructorsy A lthough constructor functions do not return values, they can

accept parameters that a client can use to pass initializationvalues to the class.

y Once you create a parameterized constructor, you have tosupply parameters when you instantiate a new object.

//Payroll.hclass Payroll{public:

Payroll(double, double);private:

double dFedTax;double dStateTax;

}

//Payroll.cpp# include Payroll.h


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# include Payroll::Payroll(double dFred, double dState){

dFedTax = dFed;dStateTax = dState;

};void main( ){

Payroll employee; //illegal

}y Constructor functions can be overloaded , just like other

functions. This means that you can instantiate different versions

of a class, depending on the suplied parametersy Being able to overload a constructor function allows you to

instantiate an object in multiple ways.//Payroll.hclass Payroll{public:

Payroll();Payroll(double dFed);Payroll(double dFed, double dState);

private:double dFedTax;double dStateTax;

}

//Payroll.cpp# include Payroll.h# include


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Payroll::Payroll(){dFedTax = 0.28;dStateTax = 0.05;

};Payroll::Payroll(double dFed){

dFedTax = dFed;};

Payroll::Payroll(double dFred, double dState){dFedTax = dFed;dStateTax = dState;

};void main( ){

Payroll employeeFL(0.28);Payroll employeeMA(0.28, 0.0595);

}Example 8.1.1

The program in this example finds the distance between two pointsusing the pointer to class objects technique.//points#include < ios tream.h>#includecla ss p oi nt {pr ivate:

int x,y;

publ ic:p oi nt( int xnew, int ynew);inl ine int getx(){

return(x);}

inl ine int gety(){


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return(y);}

d o uble f indd is t(p oi nt a, p oi nt b);};p oi nt::p oi nt( int xnew, int ynew) //parameter ized c o n s truct o r {

x = xnew;y = ynew;

}d o uble p oi nt::f indd is t(p oi nt a, p oi nt b){

d o uble temp;temp = ((b.y a.y)*(b.y a.y) + (b.x a.x)*(b.x a.x));return ( sq rt(temp));

}voi d ma in(){

d o uble value;p oi nt a o bj(4,3), b o bj(0,-1); //h ien th i g ia tr i d iem 1(4,3); d iem 2 (0, -1)p oi nt *aptr = &a o bj;p oi nt *bptr = &b o bj;aptr->get(x);aptr->get(y);bptr->get(x);bptr->get(y);value = aptr->f indd is t(a o bj, b o bj);c o ut


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Payroll::Payroll(double dFed, double dState){dFedTax = dFed;dStateTax = dState;

};You can use initialization list to rewrite the above constructor function. //ban co the khoi tao danh sach de ghi chen len cac hamdang xay dung.cau truc co dang duoi day.Payroll::Payroll(double dFed, double dState)

:dFedTax(dFed), dStateTax(dState){};

8.1.3 Parameterized Constructors that Uses DefaultArguments //xay dung tham so va doi so mac dinh

y To create a parameterized constructor that uses defaultarguments, we can put the default values at the constructor

prototype.Example 8.1.2

# includeclass Employee{private:

int idNum;double hourlyRate;

public:

Employee(const int id = 9999, const double hourly =5.65);void setValues(const int id, const double hourly);void displayValues();

};


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Employee::Employee(const int id, const double hourly){

idNum = id;hourlyRate = hourly;

}void Employee::displayValues(){

cout


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8.1.4 Copy ConstructorsThere are two ways to create a new object from an existing object.You can use either the syntax:

class new_object = e xisting_object ;

or the syntax:class new_object ( old_object );

y R egardless of which syntax you use to copy an object, itsimportant to know that no defa u lt constr u ctor e xec u tes for making the new object . I nstead, C++ uses a copy constructor toexactly copy each of the first objects data members into thesecond objects data members in an operation known as

memberwise copying .y A copy constructor is a special constructor that is called when

a new object is instantiated from an old object.y C++ supplies a default copy constructor that automatically

copies the members of the original object to the new object.y I n some situations, you must write your own copy constructor

instead of using default copy constructor.y Copy constructors are identical to standard constructors, exceptthey must accept a single call-by-reference parameter to anobject preceded by the const keyword to indicate that theoriginal object is not to be modified in any way.class_name ( const class_name & object_name );

y The call-by-reference object parameter in the copy constructor represents the object being copied.

Example 8.1.3The following code is an example of a copy constructor function for the Stocks class that dynamically allocate a new memory for the


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stock name for any new S tocks objects created by copying anexisting object.//Stocks.hclass Stocks {public:

Stocks(char* szName);Stocks(const Stocks&); //copy constructor

void setStockName(char* szName);char* getStockName();void setNumShares(int);int getNumShares(int);

void setPricePerShare(double);double getPricePerShar();double calcTotalValue();

private:char* szStockName;int iNumShares;

double dCurrentValue;double dPricePerShare;};//Stocks.cpp# include stocks.h# include #

include Stocks::Stocks(char* szName){szStockName = new char[25];strcpy(szStockName, szName);

};


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Stocks::Stocks(const Stocks& sourceStock){szStockName = new char[25];strcpy(szStockName, sourceStock.szStockName);

};void Stocks::setNumShares(int iShares){

iNumShares = iShares;}int Stocks::getNumShares(){

return iNumShares;}void Stocks::setPricePerShare(double dPrice){

dPricePerShare = dPrice;}int Stocks::getPricePerShare(){

return dPricePerShare;}void Stocks::setStockName(char* szName){

strcpy(szStockName, szName);}char* Stock::getStockName(){

return szStockName;}double Stocks::calcTotalValue(){

dCurrentValue = iNumShares*dPricePerShare;return dCurrentValue;

}void main(){

Stocks stockPick1(Cisco);stockPick1.setNumShares(100);


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stockPick1.setPricePerShare(68.875);/* The following statement creates a new object by

copying anexisting object */

St o ck s s to ckP ick2( s to ckP ick1);

stockPick2.setStockName(Lucent);stockPick2.setNumShares(200);stockPick2.setPricePerShare(59.5);cout


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y A destructor is called in two ways:o when a stack object loses scope when the function in

which it is declared ends.o when a heap object is destroyed with the delete operator.

Example 8.2.1//Stocks_02.hclass Stocks {public:

Stocks(char* szName);Stocks(const Stocks&); //copy constructor ~ St o ck s (); //destructor

void setStockName(char* szName);char* getStockName();void setNumShares(int);int getNumShares(int);void setPricePerShare(double);double getPricePerShar();

double calcTotalValue();private:

char* szStockName;int iNumShares;double dCurrentValue;double dPricePerShare;

};

//Stocks.cpp# include stocks_02.h# include


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# include Stocks::Stocks(char* szName){

szStockName = new char[25];strcpy(szStockName, szName);

};Stocks::Stocks(const Stocks& sourceStock){

szStockName = new char[25];strcpy(szStockName, sourceStock.szStockName);

};Stocks::~Stocks(){

delete [] szStockName;

cout


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return szStockName;}double Stocks::calcTotalValue(){

dCurrentValue = iNumShares*dPricePerShare;return dCurrentValue;

}void main(){

Stocks stockPick1(Cisco);stockPick1.setNumShares(100);stockPick1.setPricePerShare(68.875);Stocks* stockPick2 = new Stocks(Lucent); //heap

objectstockPick2->setNumShares(200);stockPick2->setPricePerShare(59.5);cout


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y Notice that in the above program, the destructor function iscalled only once. The stockPick1 object calls the destructor when it is destroyed by the main () function going out of scope.The stockPick 2 object does not call the destructor since it isdeclared on the heap and must be deleted manually.

y To delete the stockPick 2 object manually, add the statementdelete stockPick2; to the main () function as in the following program:

void main(){Stocks stockPick1(Cisco);stockPick1.setNumShares(100);stockPick1.setPricePerShare(68.875);Stocks* stockPick2 = new Stocks(Lucent); //heap

objectstockPick2->setNumShares(200);stockPick2->setPricePerShare(59.5);cout


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Destructor called.Destructor called.

8.3 ASSIGNMENT How assignment works when it is applied to objects???


// class declaration

class Date{private:

int month;int day;int year;

public:Date(int = 7, int = 4, int = 2001); // constructor prototype

with defaultsvoid showdate(); // member function to display a Date

};

// implementation section

Date::Date(int mm, int dd, int yyyy){

month = mm;day = dd;


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year = yyyy;}

void Date::showdate(){

cout


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y The type of assignment is called memberwise assignment .y I f the class does not contain any pointer data members , this

defa u lt assignment operator is adequate and can be used.

A ssign me nt O peratorsy A

ssignment operators , like all class members, are declared inthe class declaration section and defined in the classimplementation section.void operator= ( ClassName & );

y The keyword void indicates that the assignment function returnsno value, operator= indicates that we are overloading theassignment operator with our own version.

y The class name and & within the parentheses indicate that the parameter to the operator is a class reference.


// class declaration

class Date{

private:int month;

int day;int year;

public:Date(int = 7, int = 4, int = 2001); // constructor prototype

with defaults


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void operator=(Date&); // define assignment of a datevoid showdate(); // member function to display a date

};

// implementation section

Date::Date(int mm, int dd, int yyyy){

month = mm;day = dd;year = yyyy;

}

void Date::operator=(Date& newdate){

day = newdate.day; // assign the daymonth = newdate.month; // assign the monthyear = newdate.year; // assign the year return;

}

void Date::showdate(){

cout

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