1. Converting by assignment operator

2. Using cast operatorSyntax:(cast_type) expression;orcast_type (expression);

04/12/231 VIT - SCSE

Type Conversion

#include<iostream.h>#include<conio.h>void main(){char ch='A';int x;x=(int)ch;cout<<x;getch();}

Enum TypesThe enum keyword automatically enumerates a list of words

by assigning them values 0,1,2,3,4, and so on.

The general form of enum is:

enum variable_name{ list of constants separated by commas };

e.g:

enum day{sun,mon,tue,wed,thu,fri,sat};

04/12/232 VIT - SCSE

# include<iostream.h>

enum day{sun,mon,tue,wed,thu,fri,sat};

void main( )

{

day d1, d2,d3;

d1 = mon;

d2 = fri;

int diff = d2 – d1;

cout<<"days between = "<<diff<<endl;

if(d1<d2)

cout<< "day1 comes before day2\n";

}

04/12/233 VIT - SCSE

FunctionsA function groups a number of program statements into a

unit and gives it a name.This unit can then be invoked from other parts of the

program.It is used to reduce program size.The main advantages of using a function are:

1. Easy to write a correct small function2. Easy to read, write and debug a function3. Easier to maintain or modify such a function4. It can be called any number of times in any place with

different parameters

04/12/234 VIT - SCSE

04/12/235 VIT - SCSE

The Function DeclarationThe Function DefinitionFunction Calling

Return statement

The keyword return is used to terminate function and return a value to its caller.

The return statement may also be used to exit a function without returning a value.

The general form of the return statement is. return; return ( expression);

04/12/236 VIT - SCSE

//using multiple return statements in a function

# include<iostream.h>void main(){

float maximum( float, float, float);float x,y,z,max;cout<<"Enter three numbers";cin>>x>>y>>z;max = maximum(x,y,z);cout<<"maximum"<<max;}

float maximum(float a,float b,float c)

{

04/12/237 VIT - SCSE

if(a>b){

if(a>c)return

(a);elsereturn

(c);}else{

if(b>c)return

(b);elsereturn

(c);}

}

Types of functions

A function is invoked without passing any formal argument does not return any value to the calling portion.

A function is invoked with formal argument and does not return any value to the calling portion.

A function is invoked with formal argument and returns back a value to the calling environment.

04/12/238 VIT - SCSE

Function Arguments

The arguments can be classified into two groups:

1. Actual argument2. Formal argument

Local and Global variable

04/12/239 VIT - SCSE

A function which calls itself directly or indirectly again and again is known as the recursive function.

04/12/2310 VIT - SCSE

Recursive function

int sum(int n){int value=0;if(n= = 0)return(value);elsevalue = n+sum(n-1);return(value);} 

# include<iostream.h>void main(){int sum(int);int n,temp;cout<<"Enter any integer number"<<endl;cin>>n;temp = sum(n);cout<<"value = "<<n<<"and its sum ="<< temp;}

E.x: void sum(int a,int b,int c=6,int d=10);

04/12/2311 VIT - SCSE

Default arguments

void sum(int a1,int a2,int a3,int a4){int temp;temp = a1+a2+a3+a4;cout<<"sum="<<temp;}

// default argument declaration# include<iostream.h>void sum(int a,int b,int c=6,int d=10);

//default argument initialization

void main(){int a,b,c,d;cout<<"enter any two numbers"<<endl;cin>>a>>b;sum(a,b); //sum of default values}

04/12/2312 VIT - SCSE

Function Overloading

cout<<add(5,10);cout<<add(15,10.0);cout<<add(12.5,7.5);cout<<add(5.10,15);cout<<add(0.75,5);

int add(int a,int b);int add(int a,int b,int c);double add(double x,double y);double add(int p,double q);double add(double p,int q);

04/12/2313 VIT - SCSE

Function Overloading

double volume(double r,int h){return(3.14519*r*r*h);}long volume(long l,int b,int h){return (1*b*h);}

#include<iostream.h>int volume(int);double volume(double,int);long volume(long,int,int);main(){cout<<volume(10)<< endl;cout<<volume(2.5,8)<<endl;cout<<volume(100L,75,15);getch();return 0;}int volume(int s){return (s*s*s);}