Pointers and 3D Arrays

POINTERS AND 3D ARRAYS

In this section, we will see how pointers can be used to access a three-dimensional array. We have seen that pointer to a one-dimensional array can be declared as

int arr[]={1,2,3,4,5);

int *parr;

parr = arr;

Similarly, pointer to a two-dimensional array can be declared as

int arr [2] [2]={{1,2}, {3, 4}};

int (*parr) [2];

parr = arr;

A pointer to a three-dimensional array can be declared as

int arr [2] [2] [2]={1,2,3,4,5,6,7,8};

int (*parr) [2] [2];

parr = arr;

We can access an element of a three-dimensional array by writing,

arr[i] [j] [k] = *(*(* (arr+i)+j)+k)

Look at the code given below which illustrates the use of a pointer to a three-dimensional array.

#include <stdio.h>

#include <conio.h>

main()

{

int i,j,k;

int arr [2] [2] [2];

int (*parr) [2] [2] = arr;

clrscr();

printf("\n Enter the elements of a 2 × 2 × 2 array:");

for (i = 0; i < 2; i++)

{

for (j = 0; j < 2; j++)

{

for (k = 0; k < 2; k++)

scanf("%d", &arr[i] [j] [k]);

}

}

awode printf("\n The elements of the 2 × 2 × 2 narray are: ");

for (i 0; i < 2; i++)

{

 for (j = 0; j < 2; j++)

{

for (k = 0; k < 2; k++)

printf("%d", *(*(* (parr+i)+j)+k));

}

}

return 0;

getch();

}

Output

Enter the elements of a 2 × 2 × 2 array: 1 2 3 4 5 6 7 8

The elements of the 2 × 2 × 2 array are: 1 2 3 4 5 6 7 8

Note

In the printf statement, you could also have used * (* (* (arr+i)+j)+k)) instead of *(*(* (parr+i)+j)+k)).