Q. How to allocate a 2 dimensional array dynamically?
Ans #include <stdlib.h> /* EXIT_FAILURE, EXIT_SUCCESS */
#include <errno.h>
#include <stdio.h>
#define ROW 5
#define COL 5
int
main ( void )
{
int **cont_arr;
int **arr = malloc ( ROW * sizeof ( int * ) );
if ( !arr )
{
perror ( "Error" );
exit ( EXIT_FAILURE );
}
for ( i=0; i < ROW; i++ )
{
arr[i] = malloc ( sizeof ( int ) * COL );
if ( !arr[i] )
{
perror ( "Error" );
exit ( EXIT_FAILURE );
}
}
/*
* Contiguous memory allocated for array. Below.
*/
cont_arr = (int **) malloc ( ROW * sizeof ( int * ) );
if ( !cont_arr )
{
perror ( "Error" );
exit ( EXIT_FAILURE );
}
cont_arr[0] = (int *) malloc ( ROW * COL * sizeof ( int ) );
if ( !cont_arr[0] )
{
perror ( "Error" );
exit ( EXIT_FAILURE );
}
for ( int i=1; i < ROW; i++ )
cont_arr[i] = cont_arr[0] + i * COL;
exit ( EXIT_SUCCESS );
}