1. Introduction to Programming
Lecture 25

2. Introduction to C++
language

3. In Coming Lectures
C++ Features
Classes
Object

4. Today’s Lecture
Default Function Arguments
Inline Functions
Classes

5. Rules for Structured Programming
Do Modular programming
Write small function
Every function should perform
a specific well defined task
Function should obey single entry
single exit rule

6. Liberally Comment
the code

7. Object Oriented Language

8. Early 1980's
Bjarne Stroustrup
at Bell Labs

9. C with Classes
C++
Java

10. Default Function Arguments

11. power ( x , n ) ;

12. void f ( int i , double x ) ;

13. void f ( int i =1 , double x = 10.5 ) { -- }

14. Example 1 void f ( int i = 1 , double x = 10.5 ) {
cout<<“i = ”<<i;
cout<<“ x = “<< x<<endl; }

15. Example 1 main ( ) { f ( ) ; f ( 2 ) ; f ( 2 , 12 ) ; } Output
i = 1 x = 10.5
i = 2 x = 10.5
i = 2 x = 12

16. void f ( double x=10.5 , int i ) ;

17. The declaration of variables inside the code

18. while ( condition ) {
// body of the while loop }

19. {
int i ;
--- }

20. Scope of Variable When you declare a variable inside the block
then the variable exists in
that block.

21. Example 2 for ( int i = 0 ; i < 3 ; i++ ) { int temp = 22 ;
cout << "\n i = " << i << "temp = " << temp ; }
cout << "i = " << i ;

22. Inline functions

23. inline

24. Example 2 #define SQUARE ( X ) X * X main ( ) {
int i = 5 , j = 10 , k ; :
k = }
i + j * i + j ;
SQUARE ( i + j ) ;

25. Example 3 #define SQUARE ( X ) ( X ) * ( X ) main ( ) {
int i = 5 , j = 10 , k ;
k = }
SQUARE ( i + j ) ;
( i + j ) * ( i + j ) ;

26. Example 3 #define MAX ( A , B ) ( ( A ) > ( B ) ? ( A ) : ( B ) )
inline f ( int a, int b ) {
if ( a > b )
return a ;
return b ; }
void main ( )
int i , x , y ;
x = 23 ; y = 45 ;
i = MAX ( x++ , y++ ) ; // Side - effect : larger value incremented twice
cout << "x = " << x << " y = " << y << '\n' ;
i = f ( x++ , y++ ) ; // Works as expected

27. Function Overloading

28. Operator Overloading

29. Overloading Using the same name to perform multiple tasks or
different task depending on
the situation

30. double Intsquareroot ( int i ) ;
double Doublesquareroot ( double x ) ;

31. Example 4 int squareroot ( int i ) { // body of the function }
double squareroot ( double x )

32. Example 4 main ( ) { double i , x ; int j = 5 , k ;
i = squareroot ( 10.5 ) ;
cout << i << endl ;
k = squareroot ( j ) ;
cout << k << endl ; }

33. Example F ( int a , int b ) ; F ( int a , int b , int c ) ; main ( ) {
F ( 1 , 2 ) ; // F ( int a , int b ) ; is called
F ( 1 , 2 , 3 ) ; // F ( int a , int b , int c ) ; is called }

34. int f ( int a ) ;
double f ( int a ) ;

35. Name Mangling