C Tutorial

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Pointer in C

Pointer is a variable that is used to contain the address of another variable. We can easily create a pointer in C language. Example: int *ptr

Symbol Description
& (ampersand sign) Address of an operator is used to contain the address of a variable.
* (asterisk sign) Indirection operator is used to accesses the value at the address..
Advantage of pointer In C language, there are various advantages of pointer that are given below:
  • It is used to reduce the code and performance.
  • It accesses the direct address of the variable.
  • It is used to return multiple values from the function.
  • It helps us to access any memory location from the pointer.
      How can we declare pointer We can declare pointer by using * (astric symbol). Syntax:
int *ptr;
 char *ch;
Let us consider an example:
#include<stdio.h>
int main ()
{
int n=100;
int *ptr; // pointer variable
printf("Address of num variable: %x\n", &n);
printf("Address stored in ptr variable: %x\n", ptr ); // address stored in 
pointer variable
printf("Value of *ptr variable: %d\n", *ptr ); //access the value using the 
pointer
return 0;
}
Output
Address of num variable: f64b7adc
Address stored in ptr variable: f64b7bd0
Value of *ptr variable: 1


Null Pointer A pointer does not assign any value that is known as a NULL pointer. We can create a null pointer at the time of declaration.

Example:
int *ptr=NULL;



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