C Program to Access Array Elements Using Pointer
Objective
Write a C program to access array elements using Pointers.
Algorithm / Approach
- Declare an array
arr[5]. - Use a loop to read input. Instead of
&arr[i], use pointer arithmetic:scanf("%d", arr + i). - Use another loop to print output. Instead of
arr[i], dereference the calculated memory address:printf("%d", *(arr + i)).
main.c
#include<stdio.h>
int main( ) {
int arr[5], i;
printf("Enter Elements of Array:");
for(i=0;i<5;i++){
scanf("%d",arr+i);
}
printf("You have entered : ");
for(i=0;i<5;i++){
printf("%d ",*(arr+i));
}
return 0;
}Expected Output
Enter Elements of Array : 1 4 6 7 8 You have entered : 1 4 6 7 8
Explanation of the Program
- This proves that array indexing (
arr[i]) is just "syntactic sugar" for pointer arithmetic. - Under the hood, when you write
arr[i], the compiler translates it to*(arr + i): take the base memory address of the array, move forwardiinteger slots in memory, and fetch the data there.
Complexity
Time Complexity
O(n)
Space Complexity
O(1)
