C++ Program to Access Elements of an Array Using Pointer

Prerequisites:

• Pointers in C++
• Array in C++

A Pointer is a variable that stores the memory location or address of an object or variable. In other words, pointers reference a memory location, and obtaining the value stored at that memory location is known as dereferencing the pointer.

An Array is the collection of homogeneous elements stored in contiguous memory blocks. So, elements in an array can be accessed using a pointer.

Access elements using Pointer

Pointer has the capability to store the address, So, we can store the address of the first element of the array and then traverse the pointer till we reach the end element.

Methods to store the address of the first elements of the array are mentioned below:

• int *ptr = arr;
• int *ptr = &arr[0];

After this, a for loop is used to dereference the pointer and print all the elements and the memory location of the element of the array. At each loop iteration, the pointer points to the next element of the array. Then the array value and address are printed. Let's check the Pointer to array example.

Example:

// C++ Program to implement the
// use of pointer with array
#include <iostream>

using namespace std;

int main()
{
    int arr[5] = { 6, 2, 5, 7, 4 };

    // We can use arr or &arr[0] as both will give the
    // address of first element of the array. int *ptr =
    // arr;
    int* ptr = &arr[0];

    for (int i = 0; i < 5; i++) {
        cout << "Value of" << i << " arr[" << i << "] is "
             << *(ptr + i) << endl;
        cout << "Address of " << *(ptr + i) << " is  "
             << ptr + i << endl
             << endl;
    }
    return 0;
}

Value of0 arr[0] is 6
Address of 6 is  0x7ffc9de51fb0

Value of1 arr[1] is 2
Address of 2 is  0x7ffc9de51fb4

Value of2 arr[2] is 5
Address of 5 is  0x7ffc9de51fb8

Value of3 arr[3] is 7
Address of 7 is  0x7ffc9de51fbc

Value of4 arr[4] is 4
Address of 4 is  0x7ffc9de51fc0