Type Conversion

Type Conversion

•  Definition: The type conversion is a process in which variable in one data type can be converted to another data type.

• Some data types can be automatically converted by the compiler. This automatic conversion is called as implicit conversion.

For example :

#include<iostream>

using namespace std;

void main()

{

       int x;

       float y=99.99;

       x=y;<‒‒‒‒‒‒‒‒‒‒here value of x becomes 99 and .99 will be truncated.

}

• Similarly, we can make use of type cast to explicitly convert one type to another basic type. This type of conversion is called explicit conversion.

In C++ the type casting is done in two ways ‒

* C style type casting

* C++ style type casting

• The syntax for C style type casting is as follows ‒

(data type) expression

For example: (double) 2/3;

• The syntax for the C++ style type casting is as follows ‒

 Data type(expression)

The C++ program which illustrates the type casting is –

/*********************************************************************

Program for demonstrating the type conversion

*********************************************************************/

#include<iostream>

 using namespace std;

 void fun1()

{

       int a;

       double b,ans;

        a=2;b=11.10;

       ans (double)a*b;

       cout<<ans<<endl;

}

void fun2()

{

       int a;

       double b,ans;

       a=2; b=11.10;

       ans double(a)*b;

       cout<<ans<<endl;

}

void main()

{

       cout<<"The C style type casting"<<endl;

       fun1();

       cout<<"The C++ style type casting"<<endl;

       fun2();

}

Output

The C style type casting

22.2

The C++ style type casting

22.2

Program Explanation:

In above program the variable a is of type integer and b is of type double. When the multiplication of the two needs to be done then first we type cast the variable a to double type. The above program shows both C and C++ style type casting.