Download - c++ Tevhnical Paper Presentation With Some Changes

8/4/2019 c++ Tevhnical Paper Presentation With Some Changes

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INTRODUCTION TO C++


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fun1

fun5

fun2

fun4

fun6

fun3

Structure of procedure-oriented programs

main

Employs top-down approach


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Structure of object-oriented programs

Data membersData members

Data members

Member function

Member function

Member function

Object A Object B

Object C

Employs bottom-top approach


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Advantages of C++ over C

New data and functions can be added easily.

Programs are divided into objects rather than smaller functions.

Emphasis on data rather than procedures.

Provides data hiding i.e. data cannot be accessed by externalfunction.

Provides concept of overloading of functions and operator &inheritances which improves scope of program.


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A Simple C++ Program structure//First C++ program#include //Preprocessor directive

int main() //Function{cout


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Preprocessor directives

Lines in the program that begins with # are known as PreprocessorDirectives

The preprocessor is a program that creates modified version of theC++ source program according to directives supplied.

The compiler does not read your original source code file; it reads

the output of the preprocessor and compiles that file. You've seenthe effect of this already with the #include directive. This instructsthe preprocessor to find the file whose name follows the #includedirective, and to write it into the intermediate file at that location.

The preprocessor directives should not end with semicolon(;)

whereas every statement should end with a semicolon.

Example #include#define, #if etc.


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Functions(main) A function is self-contained block of statements that performs the desired

task.

Object oriented programs consists of mostly classes but there is always atleast one C like function main().

The execution of a program begins with main() and it ends at closing brace

{ }

The int value returned by main( ) is value returned to the operating system.

If the value returned is 0,it is the message to system that the program has

completed successfully.

If it is non zero then it is abnormal termination of program. NOTE:The default data type of main (and all function in C++) is

int

main(){ }

will give warning.


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Compilation Process [V.IMP]

.cpp

.h

Preprocessor

Processed Source

Compiler#directives processed

ParsingStatic type checking

Declarations NeededCode generationOptimizations

.obj

Object File

CompilationPhase

LinkingPhase

.obj

Object files to be linked

Libraries YouRequested

StandardLibrary

StartupModule

Linker .exe

ExecutableFile

All referencesmust be resolved!

Else, linker errors occur!

This is whencompile errors can occur!


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Program Creation

*.cpp File

Pre-Processor

*.h Files

Compiler

*.cpp File

*.h Files

Object FileStatic Library

Linker

Object File

ExecutableNote: A Static Library is a collection of object files


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DATA TYPES & OPERATORS

OPERATOR


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OPERATOR Output Operator cout


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Input Operator int x; cin>>x; The number we entered will be stored in the memory location of x. cin is object of class istream. The class istream is associated with the standard input device (i.e.

keyboard) (console i/p). The bitwise right shift operator in C is overloaded >> with cin object. No need to specify data types,as in C [Advantage]

Cascading of input operatorchar name[10];int ,rno;cin>>name>>rno;

cin reads only one word.

Note while receiving string care should be taken about space bcozit act as string terminator.


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Manipulators #include The standard library provides set of functions for manipulating the input and

output. These functions are called as manipulators.

Manipulators are operators that are used to format the data display. The most commonly used ones are endl, setw.

endl It is output stream manipulator which creates new line wherever it is placed. Its effect is same as newline character (\n).

cout


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setprecision It is used to reduces decimal points to specified values. Most of compiler round the values. General syntax for setprecision is

float x=2.999

cout


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DATA TYPES Keywords These are the special words, which is designed to do a specific task and

whose meaning is already know to compiler. Since it is predefined keyword,it cannot be used as identifiers. These words are also know as reservedwords. Many of them are common to both C & C++.

Few of them are given below.asm do for protected

auto double friend public

bool default goto register

break delete if return

case else inline

char enum long

class float new

const false operator

continue int private


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Identifiers :

Name of variables, symbolic constants, functions,arrays,classes are calledas identifiers. The predefined identifiers are known as keywords.

Variables

In C++ a variable is a place to store information. A variable is a location inyour computer's memory in which you can store a value and from whichyou can later retrieve that value.

Naming a variable

Because you can have many variables in a single program, youmust assign names to them to keep track of them. Variable names areunique. If two variables have the same name, C++ would not know to

which you referred when you request one of them.

Variable names can be as short as a single letter or as long as 32characters. Their names must begin with a letter of the alphabet but,after the first letter, they can contain letters, numbers, and underscore( _ ) characters.

Uppercase and lowercase are distinct and variables are case sensitive


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Some C++ variable types. Declaration Name Type char Character unsigned char Unsigned character

signed char Signed character (same as char) int Integer unsigned int Unsigned integer signed int Signed integer (same as int) short int Short integer unsigned short int Unsigned short integer

signed short int Signed short integer (same as short int) long Long integer long int Long integer (same as long) signed long int Signed long integer (same as long int) unsigned long int Unsigned long integer float Floating-point

double Double floating-point long double Long double floating-point


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Determing size of variables type cout


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Dynamic initializations of variables

C++ permits initializations of variables at run times. This is referred to asdynamic initializations of variables at run times.

Dynamic initializations of variables is extensively used in object-orientedprogramming. We can create exactly type of object needed, using theinformation known at run time.

e.g. int a=strlen(string);

float avg=tot/n;

Thus both declarations and initializations can be done simultaneously at theplace where the variable is used for the first time.


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Reference Variables

A reference variable is an alternative name for a variable. Ashortcut. A reference variable must be initialized to referenceanother variable. Once the reference is initialized you can treat it just like any other variable. The general form is

data type &reference-name =variable-name;

E.g.int total=100;int &sum=total;

Reference variables must be initialized at the time of declarations.

Both variable refer to same data object in memory.

NOTE: Here & is not address operator it means reference to int


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CONTROL STATEMENTS


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The Concept of Loops

You use the loop concept in everyday life. Any time you have to repeat thesame procedure, you are performing a loopjust as your computer doeswith the while statement.

While Loop [Sequential Control Statements] It is an entry controlled loop i.e. test condition is evaluated and if it is true

the body of loop is evaluated. This process is repeated until the testcondition becomes false.

General form of while is

while( test expression){Sequence of statement;}

NOTE:while(1)

{}will cause infinite loop and requires certain unconditional

statement to exit loop


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Condition is any C++ expression, and statement is any valid C++

statement or block of statements. When condition evaluates to TRUE (1),statementis executed, and then condition is tested again.

This continues until condition tests FALSE, at which timethe while loop terminates and execution continues on the first linebelow statement.

E.g.// count to 10

int x = 0;while (x < 10)cout


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WAPC++ to compute +1/2+3/4+5/6+..+99/100 using while loop

float sum=0;int i=1,j=2;

while(i


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Do-while loop [Sequential Control Statements]

On some occasion it may be necessary to execute the body of the loop,before the test is performed. Such an occasion can be handled using do-while loop.

General form of do-while loop isdo{sequence of statements;}while(test expressions) ; [NOTE]

WAPC++ to find sum of odd numbers between 1& 100.

void main(){int i=1,sum=0;do{sum=sum+i;

i=i+2;}while(i


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For Loop [Iterative Control Statements]

It is iterative control loop. It is used when no of iterations are known as compile time itself.

The general form of for loop isfor( expression 1,expression 2,expression 3){sequence of statements;

}Here expression 1 is the initial value.

expression 2 is the testing value.expression 3 is the increment (step) value.Note there is no semmicolon after the for loop.

Time delay for loopIf there is semicolon after the for loop then the loop is said to be a

software delay or do nothing for loopfor(i=0;i


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WAPC++ to find factorial of given numbervoid main()

{

int i, fact,n;coutn;

for(i=1 ,fact =1;i


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WAPC++ program to compute fibonacci series.

void main(){clrscr();

int a,b,c,n;a=0;b=1;coutn;cout


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Using for loop. Ex No 1 Ex No 2

1 1

2 2 1 2

3 3 3 1 2 3

4 4 4 4 1 2 3 4

5 5 5 5 5 1 2 3 4 5

Ex No 3(Flyod triangle) Ex No 4 (Pascals triangle)

1 1

2 3 1 2 1

4 5 6 1 3 3 1

7 8 9 10 1 4 6 4 1

Ex No 5

WAPC++ for finding sine value.


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IF Statement[ Selection Statements Or Conditional statements] This is one of the powerful conditional statement. The if statement can be

used in different can be used in different forms, depending upon the natureof the conditional test, and the main forms are:

Simple if Block if Nested if

Simple if The general form of simple statement is

if (test expression)

----------------;

e.g.

if(x>y)

cout


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Block if statement Here block of group of statements follow the test expression. The

general form isif (test expressions)

{statements;}e.g.

if( physics >=40 && chemistry>=40 && maths>=40)

{cout


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Nested if statement

This is the most important aspect of if statement in the sense it may leadto confusion if not properly used

The nested if is a statement that is the object of either if or else. Thegeneral form of nested if is,

if( test expression){

statements;}else if( test expression){statements;}

else{statements;}

The above is known as if-else ladder

T fi d l i i i t d if t t


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To find sales commission using nestedif construct

void main()

{

float sales, com;

coutsales;

if( sales


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[ ] This is multiple branching control statement , and this one is very useful

for decision making when more than one case is involved.

The general form of switch statements is switch(choice)

{case label 1:sequence statements.;break;

case label 2:sequence statements.;break;..default:statement sequence;

}//End of switch

break statement at end of each block , indicates the end of the particularcase and causes exit from switch statement, transferring control outsideswitch.

The default is optional statement is executed if no matches are found.


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Exit , Break, Continue, Goto [Jump Control Statements]

Exit The exit function causes immediate termination of the entire

program .This function stops the program execution and causes aforce return to the operating system. Because of this property this isused only for specific purposes.main(){if something

exit(1);}

Here if something is true, then the program terminates.

Break

An early exit from the loop is possible by a break statement. Whena breakstatement is encountered, the loop is immediately exited and theprogram continues with the statement immediately following theloop. The general form is ,


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while( test expression)

{

if something;

break;

}

Continue

Unlike break statement which cause the loop to be terminated thecontinue statement causes the loop to be continued with the nextiterations after skipping the statements in between, thus by passing the

rest of loop .

The general form isfor(exp1;exp2;exp3)

{

if something continue;}

e.g. for(i=0;i>no;

if(no


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goto

This is an unconditional statement. The goto statement may beused to

exit from several layers of nesting. The goto requires a label foroperations and the label must be in the same function as the gotothat uses.

The syntax is

label: //declaration syntax

goto label; //Calling

NOTE:The use of goto is highly discouraged since moregotomeans more confusion.

label:

goto label;


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ARRAYS & STRINGS


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ARRAYS An array is a collection of data storage locations, each of which holds the

same type of data. Each storage location is called an element of the array

The statementint num[5];

declares an array num of 5 components of the type int

The components are num[0], num[1], num[2], num[3], and num[4].

The general form of accessing an array component is:array_name[indexExp];

where indexExp, called index, is any expression whose value is anonnegative integer

Index value specifies the position of the component in the array.

The [ ] operator is called the array subscripting operator. The array index always starts at 0.


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One dimensional array This is also called as list. This means that an item in an array can be

accessed by just giving one subscript form of a single-dimension array istype specifier identifier-name [size]

Some basic operations performed on a one-dimensional array are: Initialize Input data Output data stored in an array Find the largest and/or smallest element

Each operation requires ability to step through the elements of the array

Easily accomplished by a loop E.g. int age[10],float marks[10],char name[10]

Array Initialization int a[5]={1,2,3,4,5}; float a[5]={1.1,2.2,3.2,4.5,5.6}; int b[ ]={1,1,2,2} In the last one size has been omitted and have been declared as an array

with 4 elements compiler automatically sizeof array.


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U i 1 D f


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Using 1-D array perform:

Ex No 1 WAPC++ to find maximum, minimum number in array and alsodetermine its location.

Ex No 2 WAPC++ to sort an array of size 10.

Ex No 3 WAPC++ to compute fibonacci series.

Ex No 4 WAPC++ to merge two array first one of size m and second oneof size n.

Ex No 5 WAPC++ that removes repeated element repeated element anddisplay it only once

e.g. {1,2,2,3,4} => {1,2,3,4}


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Two dimensional array A two dimensional array in fact, is an array of one dimensional array. A single

dimensional array can store a list of values, whereas two dimensional array canstore a table of values.It is also called as matrix

The general format istype specifier array_name[rowsize][colsize];

In two dimensional array also, element declaration (both in row and column) isdone with zero origin subscripting.

Array Initialization

Similar to one dimensional array, two dimensional array can also be initialized byfollowing their declarations with a list of initial values enclosed in braces.

e.g.int a[2][3]={1,1,1,2,2,2,}; //First row initialized to 1 and second row to 2

This can also be written as

int a[2][3]={1,1,1 },{2,2,2};


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Using 2D array perform following:

Ex No 1 WAPC++ for two dimensional array of 3*3 (matrix) to find

following Sum of all elements Row wise sum Column wise sum Sum of main diagonal

Sum of off diagonal

EX No 2 WAPC++ to perform matrix addition, subtraction, multiplication ofconformable matrices.

CHARACTER ARRAY


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CHARACTER ARRAY #include String is defined as array of character It is terminated by null character \0.

The general form of string declarations ischar string-name [size];e.g.char name[20];char address[30];

Because of null character must be equal to one plus maximum numberscharacter .

Array initializations char name[5]={t,s,e,c,\0 }; Char a[ ] ={ h,i\0};

Here a is array of three character

Reading strings scanf(%s, name); cin>>name

it reads till it encounters a blank characterto overcome this difficulty we have similar function called gets( ) which

reads the string until terminated by enter key.

gets(name);

Writing strings


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Writing strings printf(%s,name); Similar to printf function we have puts() and putchar( ) function

to write character.

String Handling Function

strcat(s1,s2) Concatenates (combines) s2 into s1

Using string handling perform:


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Using string handling perform:

EX No 1 WAPC++ to read a string and output ASCII value of eachcharacter.

EX No 2 WAPC++ to count number of es in a given string

EX No 3 WAPC++ for sorting names

EX No 4 WAPC++ to check whether given string is palindrome or not.

EX No 5 WAPC++ to delete all es present in string.e.g. tsec => tsc


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FUNCTIONS


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Functions A function is considered as fundamental building block of the language. In

order to avoid complexity of a program while coding ,debugging and testing,the program is divided into functional parts or subprograms thus, eachmodule is considered as a function.

The general form of function istype specifier function-name (argument list)argument declarations{body of function;return( expression);

}

e.g. int add( int a ,int b){return(a+b);

}

Functions Parameters


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Functions Parameters The parameters are local variablesinside the body of the function. When the function is called they will have the values passed in.

Local Variables Parameters and variables declared inside the definition of a functionare local.

They only exist inside the function body. Once the function returns, the variables no longer exist!

Block variables You can also declare variables that exist only within the bodyof a

compound statement (a block):{int block;

}//variables is destroyed after function block

Global variables


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Global variables You can declare variables outside of any function definition these

variables are global variables. Any function can access/change global variables.

Scope of variables The scope of a variable is the portion of a program where the variable has

meaning (where it exists). A global variable has global (unlimited) scope. A local variables scope is restricted to the function that declares the

variable.

A block variables scope is restricted to the block in which the variable isdeclared

Storage Class auto created each time the block in which they exist is entered. register same as auto, but tells the compiler to make as fast as

possible. static created only once, even if it is a local variable. extern global variable declared elsewhere.

Local variables are auto by default


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Local variables are auto by default. Global variables are static by default

Calling a function

Pass by value

The content of variables is copied to the formal parameters of the functiondefinition, thus preserving the contents of the arguments in the calling

funtion.

The information flows only in one way i.e. caller sends the valued to calledfunction but does not get in return unless the called function returns value.

Pass by Reference


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Pass by Reference

The formal parameter becomes reference to argument. The information flows in two way i.e. even if the calling function

does not return a value, the changes made in the variable isreflected in the caller function.Pass by value Pass by referencevoid swap(int a, int b){int t=a;

a=b;b=t;}

main()

{int a=1,b=2;swap(a,b);}

void swap(int &a, int &b)

{

int t=a;

a=b;

b=t;

}

main()

{

int a=1,b=2;

swap(a,b);

}

Passing array in function


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g yLike variables array can also be passed through function the syntax is

return type function_name(data type array-name[size]) //Declaration offunction

functionname(array name) //Calling of function

Note in declaration the size of array not know can be skipped just by declaring[ ] i.e array_name[ ]

Array name can be same or different

e.g.

int max(int a[ ] ){.}

main (){int a[5]={1,1,2,3,4},big;big=max(a);}

Function Overloading


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Function Overloading Overloading is bothing but use of same thing for different purposes. Overloaded operators a specific case of overloading General: select specific method/operator based on name, number, and type

of arguments

E.g.int add(int x);

int add (int x, int y);

int add (int x, int y, float z);

int add (double x, double y);

Rules for overloading of functions

All the functions have same name but with different sets of parameter.

The return type can be same or different.

Ambiguous definitions of functions should be avoided.

Recursive Function


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Functions can call themselves! This is called recursion.

Recursion is very usefulits often very simple to express acomplicated computation recursively.

Most common example to explain recursion is:int factorial( int x )

{

if (x == 1)

return(1);else

return(x * factorial(x-1));

}

Let say to find factorial of 3 then

3*fact(2)3*2(fact(1)

3*2*1

=>Factorial of 3=6

Using functions perform


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Using functions perform

EX No 1 WAPC++ to find maximum number in array

EX No 2 WAPC++ to find fibonacci series using recursive function.

EX No 3 WAPC++ to find GCD using recursive function.


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STRUCTURES

Structure A Structure is a container it is collection of data items or variables


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A Structure is a container, it is collection of data items or variablesof different data types that is referenced under the same name. Itprovides convenient means of keeping related information together.

Structures are used to organize related data (variables) in to a nice

neat package.

The general form of struct is,struct tag-name

{data type members;};

The tag-name identifies the particular structure and its type specifier.The field that comprise the structure are called the structure elements

Accessing members in structure You can treat the members of a struct just like variables. You need to use the member access operator '.' (pronounced

"dot").

Initialization of structure


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a a o o u u

Structure variable can also be initialized. struct stud

{

char name[10];int rno;

};

stud ={ABC,01};

struct stud{

char name[10];

int rno;

};

stud s1 ={PQR,11};

stud s2 ={XYZ,12};name

rno

struct stud

Ex No 1 WACP++ to initialize members in a structure


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Ex No 1 WACP++ to initialize members in a structure.

Array of structure The most common use of structure is array of structure. To define an array

of structures, first the structure must be defined and then the array variablemust be declared.

e.g.struct stud s[10];

This creates 10 set of variables that are organised as defined in the

structure stud .It must be remember here that like all variable, array ofstructures begin their indexing at 0.

Ex No 2 WACP++ to accept the data for 10 employees.

Structure initializations


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You can use structures just like variables:

struct stud

{char name[10];int rno;

};

struct stud s1,s2;s1.name = ABC";

s2 = s1;Above statement will initialize s2.name=ABC

Nested structure struct date

{int d,m,y;

};

struct stud


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{char name[10];int rno;

struct date dt;} ;

Ex no 3 WAPC++ to maintain student database and sort inascending order of roll no.

Structures and Function

When a structure element is passed to a function it is actuallypassing the value of that element to the function.

The general format of passing a structure to the called function is function name (structure variable name);

e.g stud s; //Object of stud display(s.name); //Passing name display(s.rno); //Passing roll no


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POINTERS

Pointers


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It is a variable which stores address of another variable. In other word, ifone variable contain the address of another, then the first variable is said topoint to the second.

Generic Pointers Sometimes we need to use pointer variables that arent associated with

a specific data type

In C++, these pointers simply hold a memory address, and arereferred to as pointers to void

Null Pointers The null pointeris a special constant which is used to explicitly

indicate that a pointer does not point anywhere

NULL is defined in the standard library (or )

In diagrams, indicated as one of:

NULL .

int *x;


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int x; x is a pointer to an integer. You can use the integer x points to in a C++ expression like this:

y = *x + 17;

*x = *x +1;

In C++ you can get the addressof a variable with the & operator

.

.

.

.

.

.

MEMORY

0

1

23

4

5

Address

123

int *x , y;y = 123;x = &y;


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int *x;

int **y;

double *z;

x some int

Pointers to anything

y some *int some int

z some double


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Pointers and Array

An array name is basically a constpointer. You can use the [] operator with a pointer:

Note x=a // gives base address of array i.e a[0] => x=&a[0];

int *x;

int a[10];

x = &a[2];

for (int i=0;i


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Pointer arithmetic

Integer math operations can be used with pointers. If you increment a pointer, it will be increased by the size of whatever it

points to.

a[0] a[1] a[2] a[3] a[4]

*ptr *(ptr+2) *(ptr+4)

int a[5];int *ptr = a;


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Pointer Parameters

Pointers are passed by value (the value of a pointer is the address it holds).

If we change what the pointer points to the caller will see the change.

If we change the pointer itself, the caller won't see the change (we get a

copy of the pointer)Pointers and String

A string is a null terminated array of characters. null terminated means there is a character at the end of the the

array that has the value 0 (null). Pointers are often used with strings:char *str = CSI;

C' S' 'I' \0

str

WAPC++ t t t i l th i i t


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WAPC++ to compute string length using pointers.

void main()

{char str[20],*ch;

int i=0;

printf(\nEnter string);

scanf(%s,str);

ch=str; //Assign base address i.e. ch=&str[0];while(*ch!=\0)

{

i++; //incrementing count

ch++; //Incrementing pointer

}printf(\n Length of string is %d :,i);


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Structure and pointers C++ permits pointers to structures, just as they allowed to any

other type of variables . Structure pointers are declared by placing * in front of structure variables name. E.g. struct stud *s; Consider the following declaration struct stud

{

char name[10];int rno;}s[2],*p;p=s would assign the base address i.e. p will point to s[0].

Member can be accessed using arrow operator ( ->)

p->namep->rno

Note p-> is another way of writing s[0]


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CLASSES AND OBJECTS

CLASSES AND OBJECTS


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CLASSES AND OBJECTS Classes extend the built-in capabilities of C++ to assist you in representing

and solving complex, real-world problems.

Class.

Class is a user define data type

A class is just a collection of variables-often of different types-combinedwith a set of related functions

A class enables you to encapsulate, or bundle, these various parts andvarious functions into one collection, which is called an object.

To declare a class, use the class keyword followed by an opening brace,and then list the data members and methods of that class. End thedeclaration with a closing brace and a semicolon.

class base{int value;};

OBJECTS


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OBJECTS Objects are instance of class

Memory is created only when objects are declared.

The fundamental purpose of an object is to provide one or morefunctions

The declaration of object is shown below

An object created is built in type variable. Once the class has beendeclared, we can create a variable of that type using the classname.

base bobj;

Access ControlA t l d fi b d t b f th l Th


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An access control defines a boundary to a member of the class. They arealso known as visibility labels and access specifiers .

A class can have three kinds of access control:

Private: Member of a class is accessible only by members and friend of theclass .By default all the members of the class is private. Protected: Member of class is accessible only by members and friends of

the class and members and friends of the derived classes, they can accessthe base member.

Public: Member of class is accessible by everyone.

Data Hiding The interface to a class is the list of public data members and methods.

The interface defines the behavior of the class to the outside world(toother classes and functions that may access variables of your class type).

The implementation of your class doesn't matter outside the class onlythe interface.

Class members


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The class can have two kind of members Data members Member functions

Data members All the primary (int, float ,char..) and the secondary data types

(arrays, pointers, structures var,..) can be the data members of aclass.

Data members are classified into two groups

Regular (auto) Static

Member Functions

A function that is defined inside a class declaration is called asmember function . In general all members are defined in the publicarea of the class It can also be defined in the private area .Memberfunctions are also called as methods.

Definitions of functions


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Defining inside Defining outside class stud

{

char name[10];int rno;

public:void getdata(){cin>>name>>rno;

}void putdata(){coutrno;

}void stud :: putdata()

{

cout


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An inline function is a function that is expanded inline when it is invoked(called). That is compiler, replaces with the corresponding function code.

The general form of inline function is inline return type function-name (arguments)

{

return.;

}

Depending on the body of function compiler decides whether to keep afunction as inline or not.

Rules for defining inline functions

main() cannot be inline.

If functions are recursive they cannot be inline. If the function contains static variables they cannot be inline.

Advantage Size of object code is considerably reduced. Increase the execution speed

Friend Function


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A friend function is non-member function, which has access toprivate and protected data of class.

Characteristics of friend function Friend functions are declared explicitly in the body of class precededby keyword friend.

Usually friend function are declared in public section, but it can bedeclared in private section also.

Friend function called be called with an object, because only data

members can be called with the objects. Friends are not member. One function can be friend of any number of classes.

Disadvantage It is not in scope of class in which it is defined.

It cannot access members name directly. Derived class does not inherit friend function. They may not be declared as static.

Static data members and members functionsIt i ibl t h i l i bl th t i h d b ll i t


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It is possible to have a single variable that is shared by all instancesof a class (all the objects). By declaring the variable as static.

Data members that are static must be declared and initialize outsideof the class. at global or file scope.

Characteristics of static data members Static variables are initialized to zero when first object is created, no

other initialization is possible.

There is only one copy of data, no matter how many objects arecreated. Thus all the objects share the same copy of the variable. The general form of declaring it is int class-name:: var-name

NOTE: The difference between global variable and staticmembers is that the static members has scope whereasglobal variables do not.

Static member functions


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Like static data members we can also declared member function as static. A static member function can be called using the class name class-name ::function-name();

Static member function can accessed only static data member.

This pointer When an object is created, the object hold only its own copy of the data

members. It does not hold the member function. There is only one copy ofmember functions exist in memory. All the object share the same copy ofthe member functions through a pointer called this .This pointer contains

the address of the object through which function is being invoked. Thecompiler automatically generates the pointer when an object is created

E.g. void putdata()

{cout


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CONSTRUCTOR DESTRUCTOR

Constructor A constructor is a special member function whose task is to initialize the


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A constructor is a special member function whose task is to initialize theobjects of the class.

The data members can also be initialized through constructors.

Characteristics of constructors They should have same name of class They can de defined either inside or outside the class with scope resolution

operator.

We cannot refer to their address. They do not have return types, even void and therefore cannot returnvalues.

They can have default arguments.

TYPES OF CONSTRUCTORS Default constructor The constructor that accepts no parameters is called as default

constructors. The default constructor of class complex

complex() ----------------Default constructor

{

The default constructor is called when an object is declared with noparameters.


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pcomplex c;

NOTE: When constructors are defined explicitly ,the default constructor

must be always be defined. Otherwise we cannot create an objectwithout parameters.

Parameterized constructor We can initialized the data members of an object when they are

created. This can be achieved through passing arguments toconstructor functions.The constructors that can take arguments are called as

Parameterized constructor.complex(int x ,int y) --------Parameterized constructor{

real=x;img=y;}

NOTE:The parameter of the constructor can be of any type except theobject of the class to which it belongs. But it can accept a referenceof an object of class as parameter. [Copy constructor]

Copy constructors When an object of the class is used to initialized another object


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When an object of the class is used to initialized another object,C++ perform a bitwise copy. That is an identical copy of the sourceobject is created in the target object with the help of constructor.That constructor is called as copy constructor.

A copy constructor takes reference to an object of the class as anargument .The process of initializations is called as copyinitializations

complex(complex &x){

real=x.real;img=x.img;

}

complex c1(1,2);

complex c2(c1); //Calling of copy constructorcomplex c3=c1; ////Calling of copy constructor

Constructor with default arguments Initializing the formal parameters is called as default argument Like


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Initializing the formal parameters is called as default argument. Likefunctions, the formal parameters of a constructor can also be initialized.

complex(int r, int im=0){

real=r;imag=im;

} The above constructor can be called with one argument. E.g. complex c1(10);

NOTE complex() complex(int x=0){ {} }

Here both the constructor can be called with no parameters. Hencecomplex c1;will generate error of ambuguity.

ALL DEFAULT CONSTRUCTOR MUST BE INITIALIZED FROM LEFT TORIGHT

Destructors


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A destructor is a special member function that is implicitly called todestroy the objects that have been created by constructor.

Destructor has same name as that of class but precedes with tilde(~) sign. Destructor will not have return type not even void. Destructor are called by itself when the object goes outside its

scope. Destructor will not have any return type, not even void.

Destructors are called in the opposite direction of constructors.

Destructor of class complex.

~complex()

{}


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INHERITANCE

CONCEPT OF INHERITANCE


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Rectangle

Triangle

Polygon

Inheritance is concept by which the properties of oneclass are avialabel to another.It allows new classes to built

from older classes, instead of being re-written.

Member acess specifier


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Member acess specifier Two levels of access control over class members

class definition inheritance typpe

The general syntax isclass DerivedClassName : access-level BaseClassName

where access-level specifies the type of derivation

private by default, or public

base class/ superclass/parent class

derived class/ subclass/

child class

derivefrom

memb

ersgoesto

Access Rights of Derived Classes


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private protected public

private - - -

protected private protected protected

public private protected public

AccessContro

l

forMembers

Type of Inheritance

The type of inheritance defines the access level for themembers of derived classthat are inherited from the base

class


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FORMS OF INHERITANCE

Single Inheritance

A

B


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Multilevel Inheritance

A

B

C


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Multiple Inheritance

A B

C


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Hierarchical Inheritance

d1 d2

B

d4d3


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Hybrid Inheritance

d 1 d2

Base

d3

MULTIPLE INHERITANCE AMBIGUITY


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What happens with duplicate methods?

class base{void draw();};

class derived :public base{void draw() ;};

derived d;d.draw(); // Error: ambiguous

Ambiguity can be resolved explicitly


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class base{void draw();

};

class derived :public base{void draw() ;};

derived d;bw.draw(); base::draw() or derived::draw()

Virtual base class can be used.

When base class is declared as virtual only one copy get inherited,thus helpingin solving problem


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OPERATOR OVERLOADING


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Operator Overloading

Uses of Operator overloading Use traditional operators with user-defined objects Straightforward and natural way to extend C++. It is mechanism which gives additional meaning to the c++ operators. When operator is overloaded, none of its original meanings are lost.

It improves the readability of the code to user and increase the scopeof the operator.

General rules for overloading of operator Only existing operator can be overload. The overloaded operator must have atleast one user-defined operand.

It is not recommended to change the basic meaning of an operator. Operator function can have default argument. All binary overloaded operators must explictily return a value.


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Restrictions on operators

Operators that can beoverloaded+ - * / % ^ & |~ ! = < > += -= *=/= %= ^= &= |= >>= [] () new deletenew[] delete[]Fig. 18.1 Operators that can be overloaded.

Arity (number of operands) cannot be changed Unary operators remain unary, and binary operators remain binary


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y p y y p y

Operators &, *, + and - each have unary and binary versions

Unary and binary versions can be overloaded separately

No new operators can be created Use only existing operators

Built-in types Cannot overload operators

You cannot change how two integers are added

Operator functions as member functions Leftmost operand must be an object (or reference to an object)of the class If left operand of a different type, operator function must be a

non-member function A non-member operator function must be a friend if private orprotected members of that class are accessed directly.

Overloading unary operators Avoid friend functions and friend classes unless absolutely necessary


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Avoid friend functions and friend classes unless absolutely necessary. Use of friends violates the encapsulation of a class. As a member function:

class add {public:void operator + ( )

...};

Pre/post-incrementing/decrementing operators Can be overloaded How does the compiler distinguish between the two? Prefix versions overloaded same as any other prefix unary operator

would be. i.e. d1.operator++();for++d1;

Postfix versions When compiler sees postincrementing expression, such as d1++; Generates the member-function call

d1.operator++( 0 );

Prototype:Date::operator++( int );

Overloaded binary operators


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Non-static member function, one argument Non-member function, two arguments

class String {public:string operator + (string s2);}; // end class String

y += z;

equivalent toy.operator+=(z);


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SIMPLE SINGLE LINKED LIST

Use of linked listO f th i d b k f i th t i f t b i d


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One of the main drawback of array is that size of array cannot be increasedor decreased during run time.

Dynamic memory allocation concepts find very useful in cases where we donot know the exact memory required.

Structural representation of simple singly linked list

A linked list is a series of connected nodes.

Each node contains at least a piece of data (any type).

Pointer points to the next node in the list

Head: pointer to the first node

The last node points to NULL

Operations of List


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Insertion: insert a new node at a particular position

Deletion: delete a node with a given value

Display: print all the nodes in the list

Search: find a node with a given value

A

node

I ti d


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Inserting a node

Steps Check for insertion at beginning Check for insertion at middle Check for insertion at end Insertion must be in sorted orders as shown.

2 4 6head //

INSERTION AT BEGINING


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2 4 6head //

HeadNew head

1

INSERTION AT MIDDLE


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2 4 5 //6

INSERTION AT END


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2 4 6 //8

Deleting a node


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Deleting a node

Steps involved in deletion of a node: Deletion in an empty linked list Head to be deleted. Middle node to be deleted

Last node to be deleted Element not found.

2 4 6head //

DELETION OF HEAD


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DELETION OF HEAD

2 4 6head //

head

DELETION OF MIDDLE


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DELETION OF MIDDLE

48 17 142head //

DELETION OF END


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DELETION OF END

48 17 142head //