Introduction
In C programming, pointers provide a powerful way to directly access and manipulate the memory locations of variables, including elements within an array. This guide will show you how to write a C program to access and display elements of an array using pointers.
Example:
- Input: Array
[1, 2, 3, 4, 5]
- Output: Displaying each element of the array using a pointer.
Problem Statement
Create a C program that:
- Takes an array of integers as input from the user.
- Uses a pointer to access and display each element of the array.
Solution Steps
- Include the Standard Input-Output Library: Use
#include <stdio.h>
for standard input-output functions. - Declare the Array and Pointer Variable: Declare an integer array to store the elements and a pointer variable for accessing the elements.
- Input the Array Elements: Use a loop to take input for the array elements from the user.
- Access and Display Array Elements Using Pointers: Use the pointer to traverse and display each element of the array.
- Display the Elements: Use
printf
to display the elements accessed by the pointer.
C Program to Access Array Elements Using Pointers
#include <stdio.h> int main() { // Step 2: Declare the array and pointer variable int arr[100], n; int *ptr; // Step 3: Input the number of elements and the array elements printf("Enter the number of elements: "); scanf("%d", &n); printf("Enter the elements of the array: "); for (int i = 0; i < n; i++) { scanf("%d", &arr[i]); } // Step 4: Initialize the pointer to point to the first element of the array ptr = arr; // Step 5: Access and display the array elements using the pointer printf("Array elements accessed using pointer: \n"); for (int i = 0; i < n; i++) { printf("Element %d: %d\n", i + 1, *(ptr + i)); } return 0; // Return 0 to indicate successful execution }
Explanation
Step 2: Declare the Array and Pointer Variable
- The integer array
arr
is declared to store the elements of the array. - The pointer
ptr
is used to access the elements of the array.
Step 3: Input the Array Elements
- The program prompts the user to enter the number of elements in the array and stores this value in
n
. - A
for
loop is used to take input for each element of the array.
Step 4: Initialize the Pointer
- The pointer
ptr
is initialized to point to the first element of the array (arr
).
Step 5: Access and Display the Array Elements Using the Pointer
- The program uses a
for
loop to traverse the array using the pointer:- The loop runs from
0
ton-1
, wheren
is the number of elements in the array. - Inside the loop, the expression
*(ptr + i)
is used to access the element at indexi
in the array by dereferencing the pointer. - The program prints each element of the array along with its position.
- The loop runs from
Return 0
- The
return 0;
statement indicates that the program executed successfully.
Output Example
Example Output:
Enter the number of elements: 5 Enter the elements of the array: 1 2 3 4 5 Array elements accessed using pointer: Element 1: 1 Element 2: 2 Element 3: 3 Element 4: 4 Element 5: 5
Conclusion
This C program demonstrates how to access and display elements of an array using pointers. It covers basic concepts such as pointer arithmetic, array traversal, and memory access, making it a useful example for beginners learning C programming.