C++ is an object-oriented programming language that is based on classes and objects. A C++ program is made up of classes, which contain methods and variables. The basic building block of a C++ program is the class. A class defines the structure and behavior of an object. Objects are instances of classes that contain their own set of properties and behaviors. The main() method acts as the entry point for program execution. C++ supports features like functions, arrays, control statements, strings and more.

1. www.SunilOS.com 1
C++
www.sunilos.com
www.raystec.com

2. www.SunilOS.com 2
C++ is a Programming Language
C++ is a programming language.
just like any other primitive language such
as C, Pascal.
It has
o Variables
o Functions
o Data Type
o Control Statement
o Arrays

3. www.SunilOS.com 3
C++ is OOP
3 Idiot
C++ is Object Oriented Programming .
follows OOP methodology.
C++ thinks only Objects.
Meri
4 Lakh
ki watch
Just like a Money Oriented Person
who always thinks of Money.

4. www.SunilOS.com 4
Basic Unit of C++ is Object
Such as program of
o sum of two numbers is an object
o Fibonacci Series is an object
o SMS Services is an object
o Email Services is an object
o Account Services is an object
Basic unit of C++ is an Object.

5. Expert Object
Each Object is an Expert object.
Expert object contains related variables and
functions.
www.SunilOS.com 5

6. An Expert never overlaps responsibilities
www.SunilOS.com 6
Creator
Preserver
Destroyer
Trimurti

7. Experts bring Modularity and Reusability
www.SunilOS.com 7

8. www.SunilOS.com 8
Object has State & Behavior
Object has state and behavior.
State will be changed by behavior.

9. www.SunilOS.com 9
Object has State & Behavior
States are stored in memory variables.
Behavior changes states.
Behaviors are implemented by functions;
functions are referred as methods in OOP
Variables and Methods of an object are
defined by Class.
Class is the structure or skeleton of an
Object.

10. Class vs Objects
www.SunilOS.com 10
Realization
Realization
State/Variables
currentGear
Speed
Color
Methods
changeGear()
Accelerator()
break()
changeColor()
State/Variables
name
address
Methods
changeName()
changeAddress()
Design
Real world entities based
on design

11. Class is the basic building block
 The basic building block of C++ is a Class.
 Also known as C with Classes.
 C++ program is nothing but a Class.
 C++ application is made of Classes.
www.SunilOS.com 11

12. www.SunilOS.com 12
Class
Class contains methods and variables.
Variables contain values of type int,
float, bool, char.
Methods perform operations.

13. Executable Program
An executable Program must have default
method ‘main’ .
Method main() is the entry point of a
Program.
main() is where program execution begins.
main() is called at runtime.
www.SunilOS.com 13

14. www.SunilOS.com 14
Program
Program Structure - Primitive Language
int i = 5 //global variable
void main(){
..
a(5);
}
void a(int k){
int j = 0; //local variable
..
}

15. www.SunilOS.com 15
Primitive Language Library
Library
Program 1 Program 2
Program 3 Program 4
 Library is made of multiple reusable programs.

16. www.SunilOS.com 16
C++ Application
ApplicationApplication
Library 1 Library 2
Library 3 Library 4
 Application is made of multiple libraries

17. www.SunilOS.com 17
C++ Program with Class
#include<iostream.h>
#include<conio.h>
class HelloCPlusPlus {
…
};
void main(){…….}
A class may contain multiple variables and
methods.
A Class should have default ‘main’ method.

18. www.SunilOS.com 18
My First Program – Hello C++
#include<iostream.h>
#include<conio.h>
void main()
{
clrscr();
cout<<“Hello C++”;
getch();
}

19. www.SunilOS.com 19
Keywords
class – is used to define a class.
public – Access modifier shows accessibility of a
class or variable or method to other classes. There
are 3 access modifiers public, protected and
private.
static – Memory for the static variables is
assigned only once in life. Non-static variables are
called instance variables.
void – is a NULL return type of main method.

20. www.SunilOS.com 20
Methods & Header Files
cout console output is used to write output at
standard device.
getch() method is used to get character.
clrscr() is used to clear console screen
clrscr() and getch() both are predefined function in
"conio.h" (console input output header file).
“iostream.h” Header that defines the standard
input/output stream objects:

21. www.SunilOS.com 21
Compile & Run Program
Save program by .cpp extension
Compile program by
o ALT+f9
Execute program by
o CTL+f9

22. Platform Dependent
www.SunilOS.com 22
Linux
Hello.cpp
Compiler
MacOSWindows
Hello.cpp Hello.cpp
CompilerCompiler

23. COUT & CIN
cout is used to print output at console.
cout<<“Enter Your Age”;
cin is used to get the data from console.
cin>>age;
Extraction operator >>
Insertion operator <<
www.SunilOS.com 23

24. www.SunilOS.com
Control Statement
if-else
while
for
do-while
GOTO
24

25. www.SunilOS.com
While Loop
25

26. www.SunilOS.com
While Loop
o bool = true;
o int round = 0;
o while ( ) {
 cout<<“ !!!";
 if(++round > 500 )
• = false;
o }
 }
 }
26

27. www.SunilOS.com
For Loop
₹10 for 5 shots
How Much?
Okay!!
27

28.  void main()
 {
 int shot;
o for (shot=1; shot <= 5; shot++)
o {
o cout<<“Shot Balloon” ;
o }
 }
www.SunilOS.com
For Loop – Five shots
28

29. www.SunilOS.com 29
Print Hello C++ 5 times - while
void main() {
o int i = 0;
o while (i < 5) {
 cout<<“Hello C++";
 i++; // i = i+1
o }
}

30. www.SunilOS.com 30
Print Hello C++ 5 times – do-while
void main(){
int i = 0;
o do {
 cout<<" Hello C++";
 i++;
o } while (i < 5);
}

31. www.SunilOS.com 31
Add.cpp
#include<iostream.h>
#include<conio.h>
void main(){
oint a = 5,b = 10;
oint sum;
osum = a + b;
ocout<<“Sum is :”<<sum;
ogetch();
}

32. www.SunilOS.com 32
C++ Data Types
Data Types:
o bool true or false
o char 1 byte
o int 4 byte
o float 4 byte
o double 8 byte
o short int 2 byte
o long int 8 byte
o wchar_t 4 byte (wide character)

33. extern
extern keyword is used to declare a variable
at any place.
Though you can declare a variable multiple
times in your C++ program
It can be defined only once in a file, a
function or a block of code.
www.SunilOS.com 33

34. extern int a, b;
extern int c;
extern float f;
int main () {
// Variable definition:
int a, b; int c; float f;
// actual initialization
a = 10; b = 20;
c = a + b;
}
www.SunilOS.com 34

35. Comments
 //Single Line Comment
/*
……….Multi Line Comment
*/
www.SunilOS.com 35

36. Constant
Fixed value that the program may not alter.
Two ways to define constant
o Using #define preprocessor.
o Using const keyword.
o outside main
 #define LENGTH 10
 #define WIDTH 5
o inside main
 const int LENGTH = 10;
 const int WIDTH = 5;
www.SunilOS.com 36

37. www.SunilOS.com 37
String.h
Create a String “Hello”;
char name[6] = { ‘V’ , ’i’ , ’j’ , ’a’ , ’y’ , ’0’ };
char name[6] = “Vijay”;

38. Functions & Purpose
strcpy(s1,s2) – copies string s2 into s1
strcat(s1,s2) – concat string s2 onto end
of s1
strlen(s1) – return length of string
strcmp(s1, s2) - Returns 0 if s1 and s2 are
the same; less than 0 if s1<s2; greater than 0 if
s1>s2.
www.SunilOS.com 38

39. www.SunilOS.com 39
Math.h
void main(){
oint a = 25;
ocout<<“Square Root ”<<sqrt(a);
ocout<<“Power ”<<pow(2,3);
ocout<<“Power ”<<abs(10);
ocout<<“Ceil ”<<ceil(2.5);
ocout<<“Floor ”<<floor(2.5);
}

40. www.SunilOS.com 40
10
One Dimension Array
20
[0]
18
..
10
8
6
4
2
[1]
[8]
[9]
[2]
[3]
[4]
[n]
length
int table[10];

41. www.SunilOS.com 41
10
Initialize an Array
20
[0]
18
..
10
8
6
4
2
[1]
[8]
[9]
[2]
[3]
[4]
[n]
length
int table[10] ;
table[0] =2;
table[1] =4;
….
Or
int table[] =
{2,4,6,8,10,12,14,16,18,20};

42. www.SunilOS.com 42
Other Data Type Arrays
char chList[10] ;
chList[0] = ‘A’….
o Or
char chList[] = {‘A’,’B’,’C’,’D’,’E’}
double douList[10] ;
douList[0] = 2.5….
o Or
double douList [] = {2.5 , 5.6 , 8.6 , 8.2}

43. www.SunilOS.com 43
One Dimension Array
int table[10];
table[0] =2;
table[1] =4;
......
table[1] =20;4B
10
[0]
[1]
[9]
length
2
4
20
1000
1000
table

44. www.SunilOS.com 44
10length
2D Array
[0]
20
18
..
10
8
6
4
2
[1]
[8]
[9]
[2]
[3]
[4]
[n]
30
27
..
15
12
9
6
3
40
36
..
20
16
12
8
4
90
81
..
45
36
27
18
9
100
90
..
50
40
30
20
10
…
[0] [1] [2] [7] [8]
9
9
..
9
9
9
9
9

45. www.SunilOS.com 45
int table[5][5];
table
1010
1000
1000
1011
1111
1010
1011
1111

46. www.SunilOS.com 46
Define an Array
int table[10][9];
table[1][5] = 5;
Passing function to array
o void functionName(int array_name[5]){
…………
…………
o }

47. Pointers
Pointer is a variable whose value is the
address of another variable.
Pointer Variable declaration
o datatype *var_name;
o int *ip;
 It stores the address of variable.
www.SunilOS.com 47

48. Operations with Pointer Variable
 int var = 20; // actual variable declaration.
 int *ip; // pointer variable
 ip = &var; // store address of var in pointer variable
 cout << var << endl; // print the address stored in ip pointer
variable
 cout << ip << endl; // access the value at the address
available in pointer
 cout << *ip << endl;
www.SunilOS.com 48

49. www.SunilOS.com 49
Function Prototype
 int sum (int, int);
 int main () {
o int total;
o total = sum (2, 3);
o printf ("Total is %dn", total);
o return 0;
 }
 int sum (int a, int b)
o {
 return a + b;
o }

50. www.SunilOS.com 50
Return a Value
 double getDivision(int a, int b)
o {
 double div = a / b;
 return div;
o }
 }

51. Disclaimer
This is an educational presentation to enhance the
skill of computer science students.
This presentation is available for free to computer
science students.
Some internet images from different URLs are
used in this presentation to simplify technical
examples and correlate examples with the real
world.
We are grateful to owners of these URLs and
pictures.
www.SunilOS.com 51

52. Thank You!
www.SunilOS.com 52
www.SunilOS.com