Pointers

Pointers

Pointers store address of variables or a memory location.

datatype *var_name;

int *ptr;

// An example pointer “ptr” that holds address of an integer variable or holds address of a memory whose value(s) can be accessed as integer values through “ptr”.

#include <stdio.h> 
void main() 
{ 
    int x = 10;
    int *ptr;
    ptr = &x;
    printf(“Value is : %d”,*ptr);
}

Since there is * in declaration, ptr becomes a pointer varaible (a variable that stores address of another variable)
Since there is int before *, ptr is pointer to an integer type variable int *ptr;& operator before x is used to get address of x. The address of x is assigned to ptr.

void main()
{
   int *p;
   int var = 10;
   p= &var;
   printf("Value of variable var is: %d", var);
   printf("\nValue of variable var is: %d", *p);
   printf("\nAddress of variable var is: %d", &var);
   printf("\nAddress of variable var is: %d", p);
   printf("\nAddress of pointer p is: %d", &p);
}

Output:
Value of variable var is: 10
Value of variable var is: 10
Address of variable var is: 0x7fff5ed98c4c
Address of variable var is: 0x7fff5ed98c4c
Address of pointer p is: 0x7fff5ed98c50

/* Pointer of integer type, this can hold the * address of a integer type variable. */

/* Assigning the address of variable var to the pointer * p. The p can hold the address of var because var is * an integer type variable. */

Problem Solving using C Language

Pointers