The type cast operator is
very important in C. Cast operator uses in convert one data type to another
data types. Type casting may be two types:
1.
Implicit type cast.
2.
Explicit type cast .
1. Implicit type cast :
In C, implicit type cast are automatically
handled by compiler i.e. when two or more data types are getting execution then
the final data-type will be that data type as it is declared, i.e it is not
depend on conversion of data type.
It is clear understand by example as:
#include<stdio.h>
#include<conio.h>
void main()
{
int i,j;
float f;
double d;
i=d*f+f*j;
}
what you
think, what will be data type of i ?
It is double!! No, right answer is int. You see in
program that double has high priority or precedence of float and int, so result
of data type will be comes in double but
when result is assign in i, it will be convert in int because
i is declared as int. It isimplicit type casting.
2. Explicit
type cast :
An explicit type cast is a cast that we should
specify invoke with either the cast. The compiler does not automatically invoke
to resolve the data type conversion.
Let's understand explicit with example:
/*A student marks of three subject as m1,m2,m3 and
calculate percentage(per)*/
#include<stdio.h>
#include<conio.h>
void main()
{
int m1=70,m2=70,m3=100,total;
float per;
total=m1+m2+m3;
per=total/300*100;
printf("%f",per);
}
output:- 0.000000
Surprise, let's explain to me, it is a common type
cast mistake, look at per=total/300*100; statement. In this
statement first of all total/300 will be solve so total(240) and 300 are int hence
240/300 will be produce a float value so result is 0.000000. These mistake may
me solved by three ways as:
1. We mention type cast in
above program as:
/*demonstration
of type casting*/
#include<stdio.h>
#include<conio.h>
void main()
{
int m1=70,m2=70,m3=100,total;
float per;
total=m1+m2+m3;
per=(float)total/300*100;
printf("%f",per);
}
output:- 80.000000
2. We used total as float variable.
#include<stdio.h>
#include<conio.h>
void main()
{
int m1=70,m2=70,m3=100;
float per,total;
total=m1+m2+m3;
per=total/300*100;
printf("%f",per);
}
output:- 80.000000
3. we convert int to float to the
300 by adding decimal portion.
#include<stdio.h>
#include<conio.h>
void main()
{
int m1=70,m2=70,m3=100,total;
float per;
total=m1+m2+m3;
per=total/300.0*100;
printf("%f",per);
}
output:- 80.000000
