TYPEDEF (TYPE DEFINITION)

TYPEDEF (TYPE DEFINITION)

            The typedef keyword allows the user to specify a new name for the existing data types.  The general format of the declaration statement using the typedef keyword is:

           

            Syntax                        :           typedef ExistingDataType NewName;

Where,

     ExistingDataType may be either a primitive data type of user-defined data type.

Note:   typedef declaration does not create any new data types.  It just adds a new name for the existing data type.

            Example:         1.         typedef int Integer;

                                                Integer x,y,z;

                                    2.         typedef char Gender;

                                                Gender x=’F’, y=’M’;

Ø  typedef keyword is very useful in the case of user-defined data types like structure.  While using typedef keyword with the structure creation, structure tag is optional.

Example:         typedef struct

                        {

                                    float real, imag;

                        }Complex;

                        Complex k;

/* EXAMPLE PROGRAM OF TYPEDEF WITH STRUCTURE */

#include<stdio.h>

#include<conio.h>

typedef struct

{

            float  real, imag;

}Complex;

main()

{

            Complex k;

            clrscr();

            printf("\nEnter Real Part:");

            scanf("%f",&k.real);

            printf("\nImaginary Part:");

            scanf("%f",&k.imag);

            printf("\nComplex Number is =%.2f + i %.2f",k.real,k.imag);

}