Integer pointer

Integer pointer only stores the address of an integer variable.



Syntax

int *pointer_name;


How to assign a variable address to the pointer?

This is also called referencing which means assigning the address of an existing variable to a pointer.

To reference a variable to the pointer, we should use & operator.


int a = 10;
int *ptr;
ptr = &a;   //here ptr references 'a'

Where,

a is an integer variable which holds the value 10.

ptr is a pointer to a variable with type integer which holds the address of variable 'a'.

Like below,

Pictorial Explanation

Integer pointer



How to access the value stored at the pointer?

Using * (asterisk) operator, we can access the value stored at the pointer.

It is also called the dereference operator which will give the value stored at the pointer.


*ptr will give the value stored at the pointer.

Example

printf("value stored at ptr = %d",*ptr);

*ptr => *(1024) => value at memory address 1024 is 10.



Animated Tutorial



Program

Example

#include<stdio.h>

int main()
{
int a = 10;
int *ptr;

ptr = &a;

printf("value of a = %d\n",a);
printf("value stored at ptr = %d\n",*ptr);
printf("Address of a = %x\n",&a);
printf("ptr points to the address = %x\n",ptr);
printf("Address of ptr = %x\n",&ptr);

return 0;
}



Output

From the above diagram.

value of a = 10
value stored at ptr = 10
Address of a = 1024
ptr points to the address = 1024
Address of ptr = 1000