Programming and Data Structures

Pointers 301

9.6 POINTERS AND TWO-DIMENSIONAL ARRAYS

A matrix can represent two-dimensional elements of an array. Details about it are explained in the

chapter 9 ] Array. Here, the first argument is row number and second column number. To display the

elements of two-dimensional array using pointer it is essential to have ' &' operator as pre-fix with an

array name followed by element numbers, otherwise compiler shows an error.

9.23 Write a program to display array elements and their address using pointers.

# include <stdio.h>

# include <canio.h>

void main ()

{

int i, j= l,*p ;

int a [3 ][3 ]= {{1 ,2 ,3 },{4 ,5 ,6 },{7 ,8 ,9 }};

clrscr();

printf ("\tElements of An Array with their addresses\n\n");

p=ba[0][0];

for (i=0,i<9,i++,j++)

I

printf ("%5d [%5u ]",*(p),p);

P++;

if(j==3)

I

printf ( " W ');

j=0;

I

I

OUTPUT:

Elements of An Array with their addresses.

1 [40521 2 [4054] 3 [4056]

4 [4058] 5 [4060] 6 [4062]

7 [4064] 8 [4066] 9 [4068]

Explanation In the above program two-dimensional array is declared and initialized. The base

address of an array is assigned to integer pointer ' p ' . While assigning the base address of two-

dimensional array, operator is to .be pre-fixed with array name followed by element numbers

which are necessary otherwise the compiler shows an error. The statement p=&a [ 0 ] [ 0 ] is used in this

context. The pointer 'p ' is printed and increased in for loop till it prints entire array elements. The i f

statement splits a line when three elements in each row are printed.