Variable Declaration and Initialization

·         C is a strongly typed language.

·         Every variable must be declared, indicating its data type before it can be used.

Examples:

·         int a=10;

·         float pt = 3.14;

·         char ch = ‘X’;

·         int a=10, b=a, c= a+b;

·         char NameStr[10] = {“Rajesh”};

·         char SurNameStr[ ] = {“Mishra”};

·         int NumArr1[5] = {10,20,30,40,50};

·         int NumArr2[] = {10,20,30,40,50};

·         int FiveNumArr1[5] = {0,0,0,0,0};

·         int FiveNumber2[5] = {0};

·         int MatixA[2][2] = {{1,2},{3,4}};

·         char MultiNameStr[3][10] = {“RaM”, “Rama”, “Rajesh”};

Pointer Initialization

Declaration of C Pointer variable

·         General syntax of pointer declaration is,

·         datatype *pointer_name;

·         Data type of a pointer must be same as the data type of the variable to which the pointer variable is pointing.

·         void type pointer works with all data types, but is not often used.

·         Here are a few examples:

int *ip     // pointer to integer variable

float *fp;      // pointer to float variable

double *dp;     // pointer to double variable

char *cp;       // pointer to char variable

 

Initialization of C Pointer variable

What is pointer initialization?

 

·         Pointer Initialization is the process of assigning address of a variable to a pointer variable.

·         Pointer variable can only contain address of a variable of the same data type.

·         In C language address operator & is used to determine the address of a variable.

#include<stdio.h>

void main()

{

    int a = 10;

    int *ptr;       //pointer declaration

    ptr = &a;       //pointer initialization

}