Answer T10

#include <stdio.h>
#include <stdlib.h>

struct Bulb
{
  int watts;
  int lumens;
};

/* function to print a Bulb */
void printBulb( struct Bulb *b )
{
  printf("watts = %d\tlumens = %d\n", b->watts, b->lumens );
}

#define length 10

int main()
{
  int j;
  
  /* declare and initialize an array of Bulb pointers */
  struct Bulb *bptr[length];
  for ( j=0; j<length; j++ ) bptr[j] = NULL;
  
  /* allocate memory for selected elements of the array */
  /* assign values to them */
  bptr[0] = (struct Bulb*)malloc( sizeof(struct Bulb) );
  bptr[0]->watts = 100; bptr[0]->lumens = 1710;

  bptr[1] = (struct Bulb*)malloc( sizeof(struct Bulb) );
  bptr[1]->watts = 100; bptr[1]->lumens = 1530;

  bptr[2] = (struct Bulb*)malloc( sizeof(struct Bulb) );
  bptr[2]->watts = 175; bptr[2]->lumens = 830;

  bptr[5] = (struct Bulb*)malloc( sizeof(struct Bulb) );
  bptr[5]->watts = 40; bptr[5]->lumens = 505;

  bptr[7] = (struct Bulb*)malloc( sizeof(struct Bulb) );
  bptr[7]->watts = 50; bptr[7]->lumens = 648;

  /* print the array */
  for ( j=0; j<length; j++ )
    if ( bptr[j] != NULL )
    {
      printf("Bulb %2d: ", j); printBulb( bptr[j] );
    }
      
  /* deallocate memory for the Bulb */
  for ( j=0; j<length; j++ )
    if ( bptr[j] != NULL )
    {
      free( bptr[j] );
    }
  
  return 0;
}