pointer operators in c
& ==> address operator
* ==> dereference operator
// Example
int a = 1;
int *ptr; // int * defines a pointer variable pointing at an int
ptr = &a; // the address of 'a' is assigned to the pointer
// 'ptr' is now equal to the address of 'a'
// when dereferenced using *, it returns the value at that address
printf("value of a: %d", *ptr); // prints "value of a: 1"poiner in c
int* pc, c, d;
c = 5;
d = -15;
pc = &c; printf("%d", *pc); // Output: 5
pc = &d; printf("%d", *pc); // Ouptut: -15poiner in c
int c, *pc;
// pc is address but c is not
pc = c; // Error
// &c is address but *pc is not
*pc = &c; // Error
// both &c and pc are addresses
pc = &c;
// both c and *pc values
*pc = c;how to make pointers in c
datatype *var;
variable var actually holds the address of the data(memory where it is stored)
*var lets you access the data stored at that addresspointer c
#include <stdio.h>
#include <stdlib.h>
int main()
{
int *ptr, i , n1, n2;
printf("Enter size: ");
scanf("%d", &n1);
ptr = (int*) malloc(n1 * sizeof(int));
printf("Addresses of previously allocated memory: ");
for(i = 0; i < n1; ++i)
printf("%u\n",ptr + i);
printf("\nEnter the new size: ");
scanf("%d", &n2);
// rellocating the memory
ptr = realloc(ptr, n2 * sizeof(int));
printf("Addresses of newly allocated memory: ");
for(i = 0; i < n2; ++i)
printf("%u\n", ptr + i);
free(ptr);
return 0;
}Copyright © 2021 Codeinu
Forgot your account's password or having trouble logging into your Account? Don't worry, we'll help you to get back your account. Enter your email address and we'll send you a recovery link to reset your password. If you are experiencing problems resetting your password contact us
