/* File: malloc4.c
  
   malloc can fail!
*/

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

main() {
   int *ptr1 ;
   int i, size, r ;

   printf ("size of array = ? ") ;
   r = scanf("%d", &size) ;
   if (r < 1) {
      fprintf(stderr, "Need an integer! Bye!\n") ;
      exit(1) ;
   }

   /* Get memory for an array using malloc */

   ptr1 = (int *) malloc(size*sizeof(int)) ;
   if (ptr1 == NULL) {
      fprintf(stderr, "malloc() failed!\n") ;
      exit(1) ;
   }


   /* Initialize array using array notation */

   for (i = 0 ; i < size ; i++) {
      ptr1[i] = i*i ;
   }


   /* Print array contents */

   printf("Array pointed by ptr1:\n") ;
   for(i = 0 ; i < size ; i++) {
      printf("%3d ", ptr1[i]) ;
   }
   printf("\n\n") ;
}